Palexia Depot (Tapentadol Prolonged-Release): Uses, Dosage & Side Effects
Twice-daily prolonged-release opioid analgesic for severe chronic pain in adults
Palexia Depot contains the active substance tapentadol in a prolonged-release matrix designed to deliver pain relief gradually over approximately 12 hours. It is prescribed for the management of severe chronic pain in adults that can only be adequately controlled with strong opioid analgesics. This evidence-based guide explains how Palexia Depot works, who should and should not take it, the correct twice-daily dosing regimen, potential side effects, clinically important drug interactions and essential safety information based on international regulatory guidance.
Quick Facts: Palexia Depot
Key Takeaways
- Palexia Depot (tapentadol prolonged-release) is a strong opioid taken twice daily at roughly 12-hour intervals for ongoing severe pain that cannot be managed with non-opioid analgesics.
- Tablets must be swallowed whole — never crushed, chewed, broken, halved or dissolved — because this would release the entire 12-hour dose at once and may cause fatal overdose.
- Tapentadol has a unique dual mechanism of action (MOR-NRI): mu-opioid receptor agonism combined with noradrenaline reuptake inhibition, which may offer better gastrointestinal tolerability than classic opioids.
- Palexia Depot carries serious risks including respiratory depression, physical dependence and addiction. It must never be combined with alcohol, benzodiazepines, gabapentinoids or MAO inhibitors.
- Do not stop Palexia Depot abruptly after prolonged use — gradual dose reduction under medical supervision is required to prevent opioid withdrawal symptoms.
What Is Palexia Depot and What Is It Used For?
Quick Answer: Palexia Depot (tapentadol prolonged-release) is a strong opioid analgesic prescribed for the management of severe chronic pain in adults when non-opioid painkillers and weaker opioids are insufficient. The prolonged-release tablet delivers tapentadol gradually over approximately 12 hours, providing sustained pain relief with twice-daily dosing and enabling continuous, round-the-clock pain control.
Tapentadol — the active substance in Palexia Depot — belongs to the class of centrally acting strong opioid analgesics. It was originally developed by Grünenthal GmbH and is approved across the European Union, the United Kingdom, Australia, and many other jurisdictions for the long-term management of severe pain. The "Depot" or "Retard" suffix signifies the prolonged-release formulation, in which the active ingredient is embedded in a matrix that gradually dissolves in the gastrointestinal tract. This design maintains steady tapentadol plasma concentrations over approximately 12 hours, in contrast to the immediate-release form (regular Palexia), which is cleared more quickly and requires dosing every 4 to 6 hours.
Palexia Depot is specifically indicated for the management of severe chronic pain in adults that requires continuous opioid treatment. Typical clinical scenarios include severe low back pain with a neuropathic component, osteoarthritis of the hip or knee unresponsive to other analgesics, neuropathic pain conditions such as painful diabetic peripheral neuropathy, chronic cancer-related pain, and persistent post-surgical pain that has transitioned to a chronic phase. Importantly, Palexia Depot is not intended for acute pain, short-term pain, as-needed pain relief, or postoperative pain in the immediate recovery period — these indications are addressed by the immediate-release formulation.
Tapentadol differs pharmacologically from traditional opioids such as morphine, oxycodone and hydromorphone. Rather than relying almost exclusively on mu-opioid receptor agonism, tapentadol simultaneously inhibits noradrenaline reuptake in the central nervous system. This dual mechanism is abbreviated MOR-NRI (mu-opioid receptor agonist – noradrenaline reuptake inhibitor). The mu-opioid component modulates ascending pain signals at supraspinal and spinal levels, while the noradrenergic component enhances descending inhibitory pain pathways in the spinal cord. Preclinical and clinical studies suggest that this synergy may allow clinically effective analgesia at lower mu-opioid receptor occupancy than equivalent doses of classical opioids, potentially translating into a more favourable tolerability profile — particularly regarding constipation, nausea and vomiting.
The 25 mg strength specifically is typically used for initial dose titration, for elderly or opioid-naive patients in whom cautious introduction is warranted, and for small incremental dose adjustments. Higher strengths (50, 100, 150, 200 and 250 mg) are available internationally to cover the full range of therapeutic doses. Because the prolonged-release tablet contains the entire 12-hour dose in a single matrix, correct handling and administration are crucial: the controlled-release mechanism must remain intact for the medicine to be used safely.
Palexia Depot does not treat the underlying cause of pain; it modulates the perception and transmission of pain signals. For this reason, treatment should form part of a multimodal pain-management strategy that may also include non-pharmacological measures (physiotherapy, psychological support, exercise therapy), non-opioid analgesics, adjuvant medications for neuropathic pain (such as gabapentinoids or certain antidepressants — used cautiously because of interaction potential), and where appropriate, treatment of comorbid mood and sleep disorders. Regular review with the prescribing physician is essential to assess ongoing benefit, tolerance, side effects and the possibility of dose reduction or discontinuation.
What Should You Know Before Taking Palexia Depot?
Quick Answer: Palexia Depot is absolutely contraindicated in people with significant respiratory depression, acute or severe bronchial asthma, paralytic ileus, acute intoxication with alcohol, hypnotics or other opioids, and in anyone taking monoamine oxidase inhibitors (MAOIs) within the past 14 days. Special caution is required in liver or kidney impairment, seizure disorders, head injury, sleep apnoea and any history of substance misuse. Tablets must always be swallowed whole.
Before Palexia Depot is prescribed, your doctor will perform a careful assessment of your general health, concurrent medications, pain history, psychological state and risk factors for opioid-related harm. Strong opioid therapy is reserved for situations in which the expected benefit clearly outweighs the recognised risks. The following sections summarise the most important safety considerations. Always provide your prescriber with a complete and honest medical history, including over-the-counter medicines, herbal remedies, alcohol use and recreational substance use, as withholding information can lead to avoidable life-threatening interactions.
Contraindications
Palexia Depot must not be used if any of the following circumstances apply to you. Your doctor will check these before initiating therapy:
- Known hypersensitivity (allergy) to tapentadol or to any of the excipients of the prolonged-release tablet.
- Any situation where opioids are contraindicated, in particular patients with significant respiratory depression, acute or severe bronchial asthma, or hypercapnia.
- Suspected or confirmed paralytic ileus (paralysis of the bowel).
- Acute intoxication with alcohol, hypnotics, other centrally acting analgesics or psychotropic substances.
- Concomitant use of monoamine oxidase inhibitors (MAOIs) or use within the last 14 days. This combination can precipitate hypertensive crisis, serotonin syndrome and cardiovascular collapse.
- Patients with severe renal impairment (creatinine clearance below 30 mL/min) — Palexia Depot has not been sufficiently studied in this population.
- Patients with severe hepatic impairment — higher and variable plasma concentrations have been observed.
- Pregnant women during labour and delivery because of the risk of respiratory depression in the newborn (prolonged-release formulations are particularly unsuitable for this setting).
Warnings and Precautions
The following conditions do not necessarily prevent treatment with Palexia Depot, but require careful individual risk assessment, possible dose adjustment, or additional monitoring. Discuss each of these openly with your doctor or pharmacist before starting therapy:
- Respiratory depression risk: Tapentadol, like all mu-opioid agonists, can suppress breathing. The risk is highest during the first 24 to 72 hours of treatment, after dose increases, in elderly or cachectic patients, those with reduced pulmonary function (chronic obstructive pulmonary disease, cor pulmonale, kyphoscoliosis), and those already receiving other central nervous system (CNS) depressants.
- Sleep-disordered breathing: Long-term opioid therapy is associated with central sleep apnoea and sleep-related hypoxaemia. If you experience morning headaches, excessive daytime sleepiness, witnessed apnoeas, loud snoring, or restless sleep, inform your doctor — a dose reduction or sleep study may be appropriate.
- Head injury and raised intracranial pressure: Opioids can elevate cerebrospinal fluid pressure and may mask clinical signs of a deteriorating neurological condition. Extra caution is needed in patients with head injury, brain tumours or impaired consciousness.
- Hepatic impairment: No dose adjustment is needed for mild liver disease. In moderate impairment, treatment should be initiated at the lowest available dose (25 mg every 24 hours), with careful monitoring and slow titration. Severe liver impairment is a contraindication.
- Renal impairment: No dose adjustment is required in mild to moderate renal impairment. In severe impairment the drug should not be used, as controlled data are lacking.
- Pancreatic and biliary tract disease: Tapentadol may provoke spasm of the sphincter of Oddi and could worsen acute pancreatitis or biliary colic.
- Seizure disorders: Tapentadol has not been systematically evaluated in patients with epilepsy and was excluded from most clinical trials. Opioids may lower seizure threshold and the risk is increased when combined with other pro-convulsant drugs.
- Mixed opioid agonists/antagonists: Medications such as pentazocine, nalbuphine, butorphanol and partial mu-opioid agonists (buprenorphine) may precipitate withdrawal and reduce the analgesic effect of Palexia Depot. Concurrent use is generally avoided.
- Endocrine effects: Chronic opioid use can lead to adrenal insufficiency and hypogonadism (with reduced libido, menstrual irregularity, erectile dysfunction and infertility). Symptoms warrant endocrine evaluation.
- Elderly patients: Older adults are more susceptible to CNS adverse effects, constipation, falls and respiratory depression. Starting with the lowest strength (25 mg) and cautious titration is recommended.
Palexia Depot tablets contain the entire 12-hour dose of tapentadol within a controlled-release matrix. If the tablet is crushed, broken, chewed, halved, cut, dissolved in liquid or otherwise compromised, the entire dose is released immediately. This can result in rapidly rising plasma concentrations, life-threatening respiratory depression and fatal overdose. Always swallow the tablet whole with at least a full glass of water. Do not use through feeding tubes unless your specialist has confirmed that the specific formulation is suitable. If swallowing whole tablets is difficult, speak to your doctor about alternative formulations or routes of administration.
Palexia Depot contains the opioid tapentadol. Repeated and prolonged use leads to tolerance (requiring higher doses for the same analgesic effect) and physical dependence. Psychological addiction — characterised by compulsive drug-seeking behaviour, use despite harm, and craving — may also occur. Risk factors include a personal or family history of substance-use disorder, current or past psychiatric illness (particularly depression and anxiety disorders), tobacco use, adolescent or young-adult age, and co-prescription of other CNS depressants. Before starting therapy you should openly discuss these risks with your prescriber. Seek medical help immediately if you find yourself needing higher doses than prescribed, taking the medicine for longer than intended, craving the medicine between doses, obtaining it from multiple sources, or using it for reasons other than pain.
Opioid-induced central sleep apnoea, sleep-related hypoxaemia, and other sleep-disordered breathing patterns may occur during chronic Palexia Depot therapy. Family members or partners may observe breathing pauses, gasping, choking or irregular breathing during sleep. If you or a household member notice such episodes — or if you experience persistent morning headaches, daytime fatigue, cognitive fog, or excessive daytime sleepiness — please inform your doctor. Dose reduction often resolves these findings. Polysomnography (sleep study) may be indicated in persistent cases.
Pregnancy, Breastfeeding and Fertility
Opioid use during pregnancy is associated with specific maternal, fetal and neonatal risks. Palexia Depot should only be used in pregnancy if alternative options have been exhausted and the benefit clearly outweighs the risk, following explicit medical guidance. Critical points include:
- Pregnancy: Do not take Palexia Depot during pregnancy unless your doctor has explicitly weighed and discussed the risks with you. Prolonged use of tapentadol during pregnancy can cause neonatal opioid withdrawal syndrome (also called neonatal abstinence syndrome, NAS), which can be life-threatening if unrecognised. Features in the newborn include high-pitched crying, irritability, hyperactivity, feeding intolerance, poor weight gain, tremor, vomiting, diarrhoea and seizures. Delivery should ideally take place in a unit experienced in managing NAS.
- Labour and delivery: Palexia Depot should not be used during labour because it may cause significant respiratory depression in the newborn. Prolonged-release formulations are particularly unsuitable in this setting because their pharmacokinetics cannot be adjusted quickly.
- Breastfeeding: Tapentadol is excreted into breast milk and may cause drowsiness, breathing difficulties and feeding problems in the nursing infant. Breastfeeding is not recommended during Palexia Depot therapy. If treatment is essential, discuss alternative infant feeding with your doctor.
- Fertility: Chronic opioid use may reduce libido, menstrual regularity and fertility in both women and men by affecting the hypothalamic-pituitary-gonadal axis. Discuss fertility concerns with your physician before long-term therapy.
Driving, Operating Machinery and Cognitive Performance
Palexia Depot can cause drowsiness, dizziness, blurred vision, confusion and impaired reaction times. These effects are most pronounced at the start of treatment, after dose increases, and when combined with alcohol or other sedating medications. Do not drive, operate heavy machinery, or undertake any task requiring sustained attention until you have established that Palexia Depot does not affect you adversely. In many jurisdictions, driving while impaired by prescription opioids carries legal consequences even when the medicine is taken as prescribed. Carry documentation of your prescription and consider travel restrictions when visiting countries with strict controlled-substance regulations.
How Does Palexia Depot Interact with Other Drugs?
Quick Answer: Palexia Depot interacts dangerously with many medicines. Absolute contraindications include MAO inhibitors (within the preceding 14 days). Severe interactions include benzodiazepines, other opioids, gabapentin and pregabalin, serotonergic drugs (SSRIs, SNRIs, tricyclics, triptans) and alcohol. Moderate interactions include barbiturates, mixed agonists/antagonists, CYP inducers and anticholinergic drugs. Always inform your doctor and pharmacist about every medicine you take.
Because tapentadol exerts effects on the mu-opioid receptor and on noradrenergic (and indirectly serotonergic) pathways, it has clinically significant interaction potential with a broad range of medications. Importantly, unlike oxycodone or codeine, tapentadol undergoes only minimal cytochrome P450 metabolism (approximately 15%), so CYP-mediated interactions are less prominent. However, pharmacodynamic interactions — where two drugs compound each other's CNS depressant, serotonergic or cardiovascular effects — are substantial and often more dangerous than metabolic interactions.
The tables below summarise the most clinically relevant drug interactions. They are not exhaustive: interactions with newer agents or uncommon medicines should be checked with your prescriber or pharmacist. Always carry an up-to-date medication list and show it to any health-care professional before starting or stopping any medicine.
Major Interactions
| Drug / Drug Class | Interaction Risk | Clinical Effect and Management |
|---|---|---|
| MAO inhibitors (phenelzine, tranylcypromine, isocarboxazid, moclobemide, selegiline, rasagiline, linezolid, methylene blue) | Contraindicated | Risk of hypertensive crisis, serotonin syndrome and cardiovascular collapse, which may be fatal. Palexia Depot must not be used within 14 days of stopping an MAOI, or started concurrently. |
| Benzodiazepines (diazepam, lorazepam, alprazolam, clonazepam, midazolam) and Z-drugs (zolpidem, zopiclone, zaleplon) | Severe | Profound sedation, respiratory depression, coma and death. Concurrent prescribing should be avoided; if unavoidable, lowest doses and shortest durations, with patient education on overdose signs and access to naloxone. |
| Other opioid analgesics (morphine, oxycodone, hydromorphone, fentanyl, methadone, codeine, tramadol) | Severe | Additive respiratory depression and sedation. Combination opioid therapy should be reserved for specialist-supervised situations (e.g. breakthrough pain in cancer). |
| Gabapentin and pregabalin | Severe | Increased risk of opioid overdose death. When both are clinically required for neuropathic pain, use the lowest effective doses and monitor closely; consider prescribing naloxone. |
| Serotonergic drugs (SSRIs, SNRIs, tricyclic antidepressants, triptans, 5-HT3 antagonists, lithium, tramadol, St John's Wort) | Severe | Serotonin syndrome: mental-status changes, autonomic instability (fever, tachycardia, hypertension), neuromuscular hyperactivity (tremor, clonus, hyperreflexia, rigidity). Can be life-threatening. Avoid where possible; if unavoidable, monitor closely and counsel patient. |
| Alcohol | Severe | Alcohol may disrupt the prolonged-release matrix (dose dumping) and potentiates sedation and respiratory depression. Complete avoidance of alcohol is required throughout treatment. |
| Illicit CNS depressants (heroin, GHB, ketamine, illegally obtained benzodiazepines) | Severe | Unpredictable and potentially fatal respiratory depression. Full disclosure to prescribing clinicians is essential for safety; harm-reduction counselling and naloxone provision may be indicated. |
Moderate Interactions
| Drug / Drug Class | Interaction Risk | Clinical Effect and Management |
|---|---|---|
| Barbiturates (phenobarbital, amobarbital, secobarbital) | Moderate–Severe | Enhanced CNS and respiratory depression. Phenobarbital is also a strong CYP inducer that may further reduce tapentadol exposure unpredictably. |
| Mixed opioid agonists/antagonists (pentazocine, nalbuphine, butorphanol) and partial mu-agonists (buprenorphine) | Moderate | May reduce the analgesic efficacy of tapentadol and could precipitate opioid withdrawal. Avoid concurrent use. |
| Strong CYP inducers (rifampicin, phenytoin, carbamazepine, efavirenz, St John's Wort) | Moderate | May reduce analgesic effect or precipitate withdrawal when inducer is started; conversely, stopping an inducer can increase tapentadol exposure. Dose may need adjustment. |
| Anticholinergic drugs (certain antidepressants, antihistamines, antipsychotics, muscle relaxants, anti-Parkinson drugs, urinary antispasmodics) | Moderate | Increased risk of severe constipation, urinary retention, paralytic ileus, dry mouth, confusion and heat intolerance, particularly in older patients. |
| Antipsychotics and sedating antihistamines | Moderate | Enhanced sedation, cognitive impairment and increased fall risk in the elderly. |
| Diuretics | Moderate | Opioids may reduce the efficacy of diuretics by inducing antidiuretic hormone release. Monitor blood pressure and fluid balance. |
| Cannabis and cannabinoid preparations | Moderate | Additive sedation, cognitive impairment, tachycardia and orthostatic hypotension. Discuss cannabis use openly with your prescriber. |
The lists above are not exhaustive. Always tell your doctor, pharmacist, dentist and anaesthetist about every medicine you take, including prescription drugs, over-the-counter remedies, vitamin and mineral supplements, herbal products, cannabis-based preparations and recreational substances. It is also sensible to inform close family members or household contacts about warning signs of opioid overdose (unresponsiveness, shallow breathing, pinpoint pupils, blue lips) so they can call emergency services if necessary. In many countries, take-home naloxone is available by prescription for patients on chronic opioid therapy.
What Is the Correct Dosage of Palexia Depot?
Quick Answer: Palexia Depot is taken twice daily at approximately 12-hour intervals. The usual starting dose for opioid-naive adults is 50 mg every 12 hours, titrated upwards according to response. The 25 mg strength is used for initial titration in elderly or sensitive patients and for small incremental adjustments. Maximum daily dose is 500 mg (250 mg twice daily). Tablets must always be swallowed whole with liquid and never crushed, split or chewed. Palexia Depot is not suitable for children under 18.
Dosing of Palexia Depot must always be individualised. Your doctor will consider your previous analgesic exposure, severity of pain, age, comorbidities (particularly hepatic or renal impairment), and risk factors for opioid-related harm. The principle of "start low, go slow" is essential: the lowest effective dose should be used for the shortest clinically appropriate duration, with regular reassessment of benefit, function and adverse effects.
Adults (18 Years and Over)
Opioid-Naive Patients
In adults not previously taking strong opioids, treatment is usually initiated at 50 mg tapentadol every 12 hours. If lower starting doses are required (e.g. in older adults or those with hepatic impairment), the 25 mg strength every 12 hours may be used. Subsequent dose increases should be in 25 mg or 50 mg increments every 12 hours, with at least 3 days between titration steps to allow steady-state levels to develop and adverse effects to be assessed.
- Take the first tablet in the morning and the second tablet approximately 12 hours later (e.g. at 07:00 and 19:00).
- Swallow the tablet whole with at least 200 mL of water. Do not crush, break, chew or dissolve.
- Palexia Depot may be taken with or without food; taking with food may reduce initial nausea.
- Do not take a double dose to compensate for a missed dose.
The total daily dose should generally not exceed 500 mg tapentadol prolonged-release (250 mg twice daily). If pain is not adequately controlled at this dose, re-evaluation by the prescriber is needed rather than further escalation.
Patients Switching from Other Opioids
When converting a patient from another strong opioid to Palexia Depot, direct milligram-to-milligram conversion tables should be applied cautiously because of incomplete cross-tolerance and inter-individual variability. The calculated equivalent dose is usually reduced by 30–50% as a safety margin, with rescue short-acting analgesia available for breakthrough pain during the transition. This process must be supervised by a prescriber experienced in opioid rotation.
Elderly Patients (Over 65 Years)
Age-Related Considerations
Although systematic pharmacokinetic studies have not shown major age-related differences in tapentadol exposure, elderly patients are more vulnerable to opioid side effects including CNS depression, respiratory depression, constipation, cognitive impairment and falls. Starting treatment at 25 mg every 12 hours with slow titration is prudent, particularly in patients over 75 years or with frailty, polypharmacy, or cognitive impairment. Regular review of the pain plan, bowel management and falls risk is essential. A comprehensive geriatric assessment may guide appropriateness of long-term opioid therapy.
Liver and Kidney Impairment
Hepatic and Renal Dose Adjustments
- Mild hepatic impairment (Child-Pugh A): No specific dose adjustment is required; standard cautious titration.
- Moderate hepatic impairment (Child-Pugh B): Start at 25 mg every 24 hours (not every 12 hours). Do not exceed 50 mg every 24 hours during the initial period. Titrate slowly with close monitoring.
- Severe hepatic impairment (Child-Pugh C): Palexia Depot should not be used.
- Mild to moderate renal impairment (creatinine clearance 30–90 mL/min): No dose adjustment is required.
- Severe renal impairment (creatinine clearance below 30 mL/min): Palexia Depot should not be used because of insufficient safety data in this population.
Children and Adolescents
Under 18 Years
Palexia Depot is not recommended for children and adolescents under 18 years of age. The safety, efficacy and appropriate dosing of the prolonged-release formulation have not been adequately established in this age group. Paediatric chronic pain should be managed in specialist centres using evidence-based multimodal approaches; when strong opioid therapy is necessary, age-appropriate formulations under paediatric pain specialist supervision are used.
Missed Dose
If you forget to take a scheduled dose of Palexia Depot, pain may return before the next dose is due. Do not take a double dose to make up for the missed one, as this can precipitate overdose. Instead:
- If you remember within a few hours of the scheduled time and it is still more than 6 hours before the next dose, take the missed tablet now.
- If the next scheduled dose is less than 6 hours away, skip the missed dose and take the next dose at the usual time.
- If you regularly forget doses, speak with your doctor or pharmacist about dosing reminders, blister packs or alternative strategies.
Overdose
Overdose of Palexia Depot is a medical emergency that can be fatal. Because of the prolonged-release formulation, toxic plasma concentrations may be reached over several hours and remain elevated for an extended period, so the clinical course may evolve slowly and recur after initial improvement. If you suspect an overdose, call emergency services immediately (112 in Europe, 911 in North America, 000 in Australia) and do not delay for symptoms to evolve.
Signs of tapentadol overdose include:
- Pinpoint pupils (miosis) — a classic opioid sign
- Severe drowsiness progressing to unresponsiveness or coma
- Shallow, slow or completely absent breathing
- Blue-tinged lips or fingertips (cyanosis)
- Cold, clammy, pale or mottled skin
- Very slow heart rate and low blood pressure
- Seizures (particularly at high doses or in overdose combinations)
- Pulmonary oedema (pink frothy sputum, severe breathlessness)
Emergency management: Place the person in the recovery position, ensure the airway is open, call emergency services, and, if available, administer naloxone (an opioid antagonist). Because tapentadol continues to be released from the prolonged-release matrix, repeated doses of naloxone or a continuous naloxone infusion may be required for many hours. The patient must be monitored in hospital even after apparent initial recovery.
Stopping Treatment and Withdrawal
Do not stop Palexia Depot abruptly after prolonged use without first consulting your doctor, even if you feel the pain has resolved. Sudden discontinuation after physical dependence has developed — which can occur within days to weeks of regular opioid therapy — may precipitate a distressing opioid withdrawal syndrome. Your doctor will design a gradual tapering schedule tailored to your dose, treatment duration and clinical situation.
Typical withdrawal symptoms, which may appear within 12 to 48 hours of stopping, include:
- Agitation, anxiety, insomnia, restlessness and irritability
- Muscle aches, joint pain, abdominal cramps
- Excessive yawning, runny nose, watery eyes, sneezing
- Dilated pupils, goose bumps, sweating, hot and cold flushes
- Nausea, vomiting, diarrhoea, loss of appetite
- Raised heart rate, raised blood pressure, raised breathing rate
- Craving for the medicine
In neonates exposed to tapentadol in utero, withdrawal may present as irritability, high-pitched cry, feeding intolerance, tremor, vomiting, diarrhoea and failure to gain weight. This is a medical emergency requiring specialist care.
What Are the Side Effects of Palexia Depot?
Quick Answer: The most common side effects of Palexia Depot (affecting more than 1 in 10 people) are dizziness, drowsiness, headache, nausea and constipation. Common side effects include decreased appetite, anxiety, sleep disturbances, vomiting, dyspepsia, dry mouth, itching and sweating. Serious but less common side effects include respiratory depression, serotonin syndrome, severe allergic reactions, seizures and sleep apnoea. Seek immediate medical attention for breathing difficulties, facial swelling, severe rash, seizures, or a person who cannot be roused.
As with all medicines, Palexia Depot can cause side effects, although not everyone will experience them. Side effects are grouped below by how often they occur, using the standard MedDRA frequency categories. Many adverse effects are dose-related and tend to improve or resolve within 1 to 2 weeks as the body adjusts to the medicine (tolerance develops to most opioid side effects except constipation and miosis). Preventive bowel management — adequate fluid intake, fibre, and stimulant or osmotic laxatives as recommended by your prescriber — is generally advisable from day one of treatment.
- Breathing that is abnormally slow, shallow or has stopped
- Severe drowsiness, pinpoint pupils, or inability to rouse someone who has taken Palexia Depot
- Facial, lip, tongue or throat swelling, hives, difficulty breathing or wheeze (suggestive of anaphylaxis)
- Seizures (convulsions)
- Serotonin syndrome: high fever, agitation, confusion, rapid heart rate, muscle twitching or rigidity, excessive sweating, tremor
- Chest pain, fainting or severe dizziness
Very Common
May affect more than 1 in 10 people
- Dizziness
- Drowsiness (somnolence)
- Headache
- Nausea
- Constipation
Common
May affect up to 1 in 10 people
- Decreased appetite
- Anxiety, confusional state, hallucinations, abnormal dreams
- Insomnia, sleep disturbance
- Tremor, involuntary muscle contractions
- Flushing
- Vomiting, diarrhoea, dyspepsia, dry mouth, abdominal discomfort
- Pruritus (itching), sweating (hyperhidrosis), rash
- Muscle spasms, musculoskeletal discomfort
- Asthenia (weakness), fatigue
- Feeling of body temperature change, feeling jittery, irritability
Uncommon
May affect up to 1 in 100 people
- Depressed mood, disorientation, nervousness, restlessness, euphoric mood
- Drug dependence, attention disturbances, memory impairment
- Sedation, disturbance in coordination, dysarthria (slurred speech), hypoaesthesia (numbness), paraesthesia (tingling), muscle twitching
- Visual disturbances, blurred vision
- Increased or decreased heart rate, palpitations, hypotension (low blood pressure)
- Respiratory depression, oxygen desaturation, dyspnoea (breathlessness)
- Urticaria (hives), abdominal pain
- Urinary hesitation, pollakiuria (frequent urination), urinary retention
- Drug withdrawal symptoms, oedema (swelling), feeling abnormal or drunk, feeling of relaxation
- Elevation of liver enzymes in blood tests
Rare
May affect up to 1 in 1,000 people
- Hypersensitivity reactions including angioedema, anaphylaxis and anaphylactic shock
- Abnormal thinking, seizures, reduced level of consciousness
- Syncope (fainting), impaired coordination, presyncope
- Bradycardia (slow heart rate)
- Delayed gastric emptying
- Pollakiuria with overflow incontinence
- Sexual dysfunction, amenorrhoea
Frequency Not Known
Cannot be estimated from available data
- Delirium
- Serotonin syndrome
- Central sleep apnoea syndrome
- Secondary adrenal insufficiency
- Androgen deficiency, hypogonadism
- Neonatal opioid withdrawal syndrome (when used in pregnancy)
People living with chronic pain are at elevated risk of depression, anxiety and suicidal thoughts independently of any analgesic therapy. Some antidepressants that affect serotonin may also transiently raise suicidality risk, particularly in the first weeks of treatment and in younger adults. Although tapentadol itself has not been shown to increase suicidal ideation in clinical data, vigilance is appropriate. If you experience persistent low mood, hopelessness, thoughts of self-harm or suicide, contact your doctor or a mental-health crisis service immediately. In many countries, 24-hour crisis helplines are available.
If you notice any side effects — including any not mentioned above, or changes in how the medicine is working — talk to your doctor, pharmacist or nurse. You can also report suspected side effects directly to your national pharmacovigilance authority (e.g. MHRA Yellow Card in the UK, FDA MedWatch in the USA, EMA EudraVigilance across the EU). Individual reports help regulators monitor the safety of medicines in real-world use.
How Should You Store Palexia Depot?
Quick Answer: Store Palexia Depot in its original blister pack, out of sight and reach of children, in a secure location where no-one else can access it (ideally a lockable cabinet). No special temperature or humidity conditions are required. Do not use after the expiry date printed on the carton. Return unused or expired tablets to your pharmacy for safe destruction — never throw opioid medicines in household waste or flush them down the drain.
Because Palexia Depot is a strong opioid medication, safe storage is critically important. Accidental ingestion by a child or a person for whom the drug was not prescribed can cause fatal respiratory depression, even with a single tablet. Diversion of opioid medications to non-medical use is also a significant public-health concern. The following practical measures minimise both accidental and intentional harm:
- Out of sight and reach of children: Store above eye level in a secure cupboard or lockbox. Do not leave tablets on bedside tables, kitchen counters or in handbags accessible to children.
- Secure storage: In households with other adults, adolescents or visitors, consider a locked medicine cabinet or personal lockbox. In some jurisdictions, locked storage is recommended or required for Schedule II controlled substances.
- Original packaging: Keep tablets in the original blister strips within the labelled carton. This preserves the integrity of the prolonged-release matrix, protects from light and moisture, and ensures the expiry date and batch information remain visible.
- No special storage conditions: Palexia Depot does not require refrigeration or specific temperature control. Normal room temperature is satisfactory.
- Expiry date: Do not use Palexia Depot after the expiry date (marked "EXP" on the carton and blister). The expiry date refers to the last day of that month.
- Travel: When travelling internationally, carry tapentadol in its original container with the prescription label. Many countries regulate opioid importation; carry a signed prescription and, if visiting countries with strict controls (e.g. Japan, United Arab Emirates, Singapore), check embassy requirements before travel.
Return any unused, expired or leftover Palexia Depot tablets to your community pharmacy for safe destruction under national medicines-disposal schemes. Do not throw them in household rubbish (accessible to children and waste handlers), do not flush them down the toilet or sink (environmental contamination), and do not give them to family or friends (illegal in most jurisdictions and potentially fatal). In the United States, the DEA sponsors periodic National Prescription Drug Take Back Days; many communities also have permanent drug take-back kiosks at pharmacies and police stations.
What Does Palexia Depot Contain?
Quick Answer: Each Palexia Depot 25 mg prolonged-release tablet contains 25 mg tapentadol (equivalent to 29.12 mg tapentadol hydrochloride) as the active ingredient. The prolonged-release matrix is built from polymeric excipients that control the gradual release of tapentadol over approximately 12 hours. The tablet also contains pharmaceutical excipients for tablet structure and film coating.
Active Ingredient
Each prolonged-release tablet contains 25 mg tapentadol, provided as 29.12 mg tapentadol hydrochloride. Higher strengths sold under the same brand in many countries contain 50, 100, 150, 200 or 250 mg tapentadol.
Inactive Ingredients (Excipients)
The excipients serve specific pharmaceutical functions in the prolonged-release tablet. While the exact composition may vary slightly by market, the following ingredients are typical:
- Prolonged-release matrix and tablet core: hypromellose (hydroxypropyl methylcellulose) or similar polymeric release-controlling agent, microcrystalline cellulose, colloidal anhydrous silica, magnesium stearate.
- Film coating: polyvinyl alcohol, titanium dioxide (E 171), macrogol 3350, talc, and colouring agents specific to the strength (iron oxides or lakes) to enable visual distinction between dose strengths.
If you know you are allergic or intolerant to any excipient, review the full list in the patient information leaflet enclosed with your medicine. Palexia Depot contains less than 1 mmol sodium (23 mg) per tablet and is essentially sodium-free. The 25 mg prolonged-release formulation does not contain lactose in most European and UK marketed products, but composition may differ between manufacturers and countries — always check the specific leaflet for your product if you have a confirmed lactose intolerance.
Appearance and Pack Sizes
Palexia Depot 25 mg prolonged-release tablets are typically small, round or oblong, film-coated tablets embossed with a strength-specific code identifying the manufacturer. They are supplied in blister packs, commonly in pack sizes of 10, 14, 20, 28, 30, 50, 56, 60 or 100 tablets. Not all pack sizes are marketed in every country. Refer to the carton and patient information leaflet supplied with your prescription for the exact appearance and pack configuration.
Marketing Authorisation Holder and Manufacturer
The marketing authorisation holder for Palexia Depot in Europe is Grünenthal GmbH, Zieglerstrasse 6, 52078 Aachen, Germany. Manufacturing sites may differ by country; the specific manufacturer is listed on the pack and patient information leaflet. In the United States, prolonged-release tapentadol is marketed under the brand name Nucynta ER by different authorisation holders. Generic prolonged-release tapentadol formulations are increasingly available in Europe and other markets following patent expiry.
Frequently Asked Questions About Palexia Depot
Palexia Depot (tapentadol prolonged-release) is a strong opioid analgesic used for the management of severe chronic pain in adults that cannot be adequately controlled with non-opioid painkillers. Typical indications include severe chronic low back pain with a neuropathic component, painful osteoarthritis of the hip or knee, painful diabetic peripheral neuropathy, cancer-related pain and chronic post-surgical pain. The prolonged-release formulation provides sustained analgesia over approximately 12 hours with twice-daily dosing and is therefore designed for continuous, round-the-clock pain control — not for acute pain or as-needed relief.
No. Palexia Depot tablets must always be swallowed whole with sufficient water. Crushing, breaking, chewing, halving, cutting, dissolving or otherwise compromising the prolonged-release matrix will destroy the controlled-release mechanism. This releases the entire 12-hour dose of tapentadol at once, producing very high plasma concentrations that can cause life-threatening respiratory depression, overdose and death. If you have difficulty swallowing whole tablets, contact your prescribing doctor immediately to discuss alternative formulations or routes of administration — never improvise with the existing tablets.
Both products contain tapentadol, but the formulations differ significantly. Regular Palexia is an immediate-release film-coated tablet that dissolves quickly in the stomach, with peak plasma concentrations within about 1.25 hours and a short duration of action (4 to 6 hours). It is used for acute pain with flexible on-demand dosing. Palexia Depot embeds tapentadol in a prolonged-release matrix that dissolves gradually, reaching peak concentrations between 3 and 6 hours and maintaining therapeutic plasma levels for roughly 12 hours with twice-daily dosing. Palexia Depot is used for chronic pain requiring continuous opioid coverage. The two formulations are not interchangeable milligram-for-milligram and should never be substituted without medical supervision.
Yes. Palexia Depot contains tapentadol, a strong opioid. Regular or prolonged use produces tolerance (requiring higher doses for the same effect), physical dependence (withdrawal symptoms if stopped abruptly), and may lead to psychological addiction with compulsive use despite harm. Risk factors include a personal or family history of substance-use disorder, concurrent or past depression or anxiety, tobacco use, and co-prescription of other CNS depressants. Risk is reduced by using the lowest effective dose, taking the medicine exactly as prescribed, not sharing it with others, and regular review with the prescriber. If concerning signs emerge — needing larger doses, taking extra tablets, obtaining the medicine from multiple sources, or craving between doses — seek medical help promptly.
No. Alcohol must be avoided completely throughout treatment with Palexia Depot. Two concerns apply. First, alcohol has pharmacodynamic additive effects with opioids, amplifying sedation, respiratory depression and the risk of fatal overdose. Second, alcohol can destabilise the prolonged-release matrix of tapentadol tablets (a phenomenon termed "dose dumping"), causing the 12-hour dose to be released in minutes and producing rapidly rising plasma levels. Even small amounts of alcohol may be unsafe. If you have alcohol-dependence concerns, discuss this openly with your doctor — both conditions can be addressed together with appropriate clinical support.
Palexia Depot should not be used during pregnancy unless your doctor has specifically concluded that the benefit outweighs the risk and no suitable alternative exists. Prolonged use during pregnancy can cause potentially life-threatening neonatal opioid withdrawal syndrome (NAS) in the newborn. It must not be used during labour because it may cause neonatal respiratory depression — the prolonged-release pharmacokinetics make dose adjustment impossible in an obstetric emergency. Tapentadol is excreted into breast milk and can cause sedation, feeding problems and breathing difficulty in the nursing infant, so breastfeeding is not recommended while on Palexia Depot. If you are planning pregnancy or could become pregnant, discuss contraception and pain-management alternatives with your prescriber.
Overdose of Palexia Depot is a medical emergency. Because the tablets release tapentadol slowly over many hours, symptoms may be delayed and prolonged. Features include pinpoint pupils, severe drowsiness or unresponsiveness, shallow or stopped breathing, blue lips, cold clammy skin, low blood pressure, seizures and cardiac arrest. Call emergency services immediately (112 in Europe, 911 in North America, 000 in Australia), place the person in the recovery position and keep the airway clear. If naloxone is available, administer it as instructed — but remember that because tapentadol continues to release from the tablet matrix, repeated naloxone doses or a continuous naloxone infusion may be required and the person must be observed in hospital for many hours even after apparent initial recovery.
References
This article is based on international medical guidelines and peer-reviewed scientific literature. Key sources include:
- European Medicines Agency (EMA). Tapentadol Prolonged-Release Summary of Product Characteristics (SmPC). Available at: www.ema.europa.eu.
- U.S. Food and Drug Administration (FDA). Nucynta ER (tapentadol extended-release) Prescribing Information. Available at: www.accessdata.fda.gov.
- World Health Organization (WHO). WHO Guidelines for the Pharmacological and Radiotherapeutic Management of Cancer Pain in Adults and Adolescents. Geneva: WHO; 2018.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List (2023). Geneva: WHO; 2023.
- Tzschentke TM, Jahnel U, Kogel B, et al. Tapentadol hydrochloride: a next-generation, centrally acting analgesic with two mechanisms of action in a single molecule. Drugs of Today. 2009;45(7):483–496. doi:10.1358/dot.2009.45.7.1395291.
- Hartrick CT, Rozek RJ. Tapentadol in pain management: a mu-opioid receptor agonist and noradrenaline reuptake inhibitor. CNS Drugs. 2011;25(5):359–370.
- Afilalo M, Etropolski MS, Kuperwasser B, et al. Efficacy and safety of tapentadol extended release compared with oxycodone controlled release for the management of moderate to severe chronic pain related to osteoarthritis of the knee: a randomized, double-blind, placebo- and active-controlled phase III study. Clin Drug Investig. 2010;30(8):489–505.
- Buynak R, Shapiro DY, Okamoto A, et al. Efficacy and safety of tapentadol extended release for the management of chronic low back pain: results of a prospective, randomized, double-blind, placebo- and active-controlled Phase III study. Expert Opin Pharmacother. 2010;11(11):1787–1804.
- Schwartz S, Etropolski M, Shapiro DY, et al. Safety and efficacy of tapentadol ER in patients with painful diabetic peripheral neuropathy: results of a randomized-withdrawal, placebo-controlled trial. Curr Med Res Opin. 2011;27(1):151–162.
- National Institute for Health and Care Excellence (NICE). Chronic pain (primary and secondary) in over 16s: assessment of all chronic pain and management of chronic primary pain. NICE guideline NG193. 2021.
- British National Formulary (BNF). Tapentadol Monograph. Available at: bnf.nice.org.uk.
- Dowell D, Ragan KR, Jones CM, Baldwin GT, Chou R. CDC Clinical Practice Guideline for Prescribing Opioids for Pain – United States, 2022. MMWR Recomm Rep. 2022;71(RR-3):1–95.
- Wiffen PJ, Derry S, Naessens K, Bell RF. Oral tapentadol for cancer pain. Cochrane Database Syst Rev. 2015;(9):CD011460.
- Santos J, Alarcao J, Fareleira F, et al. Tapentadol for chronic musculoskeletal pain in adults. Cochrane Database Syst Rev. 2015;(5):CD009923.
- Riemsma R, Forbes C, Harker J, et al. Systematic review of tapentadol in chronic severe pain. Curr Med Res Opin. 2011;27(10):1907–1930.
Medical Editorial Team
This article was written and reviewed by the iMedic Medical Editorial Team, which includes board-certified physicians specialising in clinical pharmacology, pain medicine, anaesthesiology and internal medicine. Our content follows the GRADE evidence framework and adheres to international guidelines from the WHO, EMA, FDA, NICE and major pain-medicine societies. All medicines content is independently reviewed without sponsorship from pharmaceutical companies.
Evidence Standard
Level 1A – Based on systematic reviews, meta-analyses, Cochrane reviews and international treatment guidelines from WHO, EMA, FDA, NICE and BNF.
Editorial Independence
No pharmaceutical company sponsorship or advertising. All content is independent and free from commercial influence. Last reviewed 12 January 2026.