Thiamine Kabi (Vitamin B1): Uses, Dosage & Side Effects
High-dose parenteral thiamine for the treatment of Wernicke's encephalopathy and severe vitamin B1 deficiency
Quick Facts About Thiamine Kabi
Key Takeaways About Thiamine Kabi
- First-line therapy for Wernicke's encephalopathy: High-dose intravenous thiamine (typically 500 mg three times daily) is the cornerstone of treatment for this potentially fatal neurological emergency caused by vitamin B1 deficiency
- Always give thiamine before glucose: Administering intravenous dextrose to a thiamine-deficient patient can precipitate or worsen Wernicke's encephalopathy. Parenteral thiamine must be given first or simultaneously in at-risk patients
- Rare but serious anaphylaxis risk: Intravenous thiamine can cause rare anaphylactoid reactions. Administration requires immediate access to resuscitation equipment and trained staff
- Slow IV administration: Thiamine Kabi should be given as a slow intravenous injection over at least 10 minutes, or diluted in 100 ml of sodium chloride 0.9% for infusion
- Essential for high-risk groups: Alcohol use disorder, chronic malnutrition, hyperemesis gravidarum, refeeding syndrome, bariatric surgery, and cancer patients receiving chemotherapy are key groups requiring thiamine replacement
What Is Thiamine Kabi and What Is It Used For?
Thiamine Kabi is an injectable solution of thiamine hydrochloride (vitamin B1) 50 mg/ml. It is used to treat and prevent severe thiamine deficiency, most notably Wernicke's encephalopathy, Korsakoff syndrome, and beriberi. It is given intravenously or intramuscularly by healthcare professionals when oral supplementation is insufficient, unreliable, or impossible due to the severity of the clinical condition.
Thiamine, also known as vitamin B1 or aneurine, is a water-soluble vitamin essential for carbohydrate metabolism and the normal functioning of the nervous, cardiovascular, and muscular systems. The human body cannot synthesise thiamine, so daily intake from food (such as whole grains, legumes, pork, and fortified cereals) or supplementation is required. After absorption in the small intestine, thiamine is phosphorylated to thiamine pyrophosphate (TPP, also called thiamine diphosphate), which is the biologically active coenzyme form. TPP is a critical cofactor for three key enzymes: pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase in the Krebs cycle, and transketolase in the pentose phosphate pathway.
Because tissues with a high glucose metabolism, such as the brain and the heart, are particularly dependent on thiamine-dependent enzymes, thiamine deficiency first manifests as neurological and cardiovascular dysfunction. Body stores of thiamine are small (approximately 25–30 mg in a healthy adult) and can be depleted within 2–3 weeks of inadequate intake, accelerated metabolism, or increased losses. In many developed countries, thiamine deficiency is most often seen in people with chronic alcohol use disorder, severe malnutrition, prolonged vomiting, chronic dialysis, after bariatric surgery, and during the refeeding of malnourished patients.
Thiamine Kabi is indicated for the treatment and prevention of severe thiamine deficiency where parenteral administration is necessary. Its principal clinical uses include:
- Wernicke's encephalopathy: an acute, potentially fatal neurological syndrome characterised by the classic triad of confusion, ataxia (unsteady gait), and ophthalmoplegia (eye movement abnormalities including nystagmus)
- Korsakoff syndrome: a chronic, largely irreversible memory disorder that can follow untreated or inadequately treated Wernicke's encephalopathy
- Beriberi: including both wet beriberi (high-output cardiac failure with peripheral oedema) and dry beriberi (symmetrical peripheral neuropathy)
- Alcohol use disorder: for prevention of Wernicke–Korsakoff syndrome during alcohol withdrawal or treatment of established deficiency
- Severe malnutrition and refeeding syndrome: including patients with anorexia nervosa, chronic gastrointestinal disease, or prolonged intravenous nutrition without adequate thiamine supplementation
- Hyperemesis gravidarum: for prevention of maternal Wernicke's encephalopathy in pregnant women with severe, persistent vomiting
- Post-bariatric surgery complications: particularly after Roux-en-Y gastric bypass or sleeve gastrectomy where malabsorption and inadequate intake can cause deficiency
- Chemotherapy-induced thiamine deficiency: notably with 5-fluorouracil, which inhibits thiamine phosphorylation
Untreated Wernicke's encephalopathy has a mortality rate of approximately 17%, and around 80% of survivors develop permanent Korsakoff syndrome with severe anterograde amnesia and confabulation. Early recognition and immediate parenteral thiamine replacement can reverse many of the neurological deficits if initiated within hours of symptom onset. The classic clinical triad is present in only about 10% of cases, so clinicians should maintain a low threshold for empirical treatment in any at-risk patient with unexplained neurological symptoms.
Thiamine Kabi contains 50 mg/ml of thiamine hydrochloride, which allows the administration of high therapeutic doses (typically 100–500 mg per dose) in a small, clinically practical volume. Because chronic oral absorption of thiamine in thiamine-deficient states is limited to approximately 5 mg per day even at high oral doses, the parenteral route is essential in patients with acute severe deficiency or suspected Wernicke's encephalopathy. Oral thiamine supplementation alone cannot reliably replace body stores fast enough in these situations.
What Should You Know Before Receiving Thiamine Kabi?
Before receiving Thiamine Kabi, the prescribing clinician must screen for prior hypersensitivity to thiamine, history of severe allergic reactions, atopy, and concomitant medications. Thiamine Kabi should only be administered in settings where cardiopulmonary resuscitation is immediately available. In patients at risk of thiamine deficiency, thiamine must be given before any intravenous glucose-containing fluids to prevent precipitating Wernicke's encephalopathy.
Contraindications
Thiamine Kabi must not be administered in the following circumstances:
- Known hypersensitivity to thiamine or any excipient: Patients who have had a previous severe anaphylactic or anaphylactoid reaction to thiamine must not receive Thiamine Kabi. Cross-reactivity with other B-complex vitamins has been reported but is rare
- Previous documented severe allergic reaction to parenteral thiamine: Even mild reactions in the past should prompt careful risk–benefit assessment, and alternative administration routes or slower titration may be required under medical supervision
Warnings and Precautions
The following precautions must be observed whenever Thiamine Kabi is prescribed or administered:
- Risk of anaphylactoid reactions: Rare but potentially fatal hypersensitivity reactions have been reported, particularly following rapid intravenous injection. These can include bronchospasm, angioedema, cyanosis, hypotension, cardiovascular collapse, and cardiac arrest. Resuscitation facilities (oxygen, adrenaline/epinephrine, antihistamines, corticosteroids, intubation equipment) and trained personnel must be immediately available during and after administration
- Slow intravenous administration: Bolus intravenous injection must be given slowly, typically over at least 10 minutes, to minimise the risk of hypotension and hypersensitivity. Intravenous infusion diluted in 100 ml of saline or glucose 5% is generally preferred
- Alcohol use disorder and glucose administration: Patients with chronic alcohol use or poor nutritional status have depleted thiamine reserves. Administration of intravenous glucose before thiamine can consume remaining thiamine stores in glucose metabolism and precipitate or exacerbate Wernicke's encephalopathy. In all such patients, parenteral thiamine should be given before or simultaneously with glucose-containing fluids
- History of atopy or multiple drug allergies: Patients with asthma, atopic dermatitis, previous angioedema, or multiple drug allergies may be at increased risk of anaphylactoid reactions and require enhanced monitoring during administration
- Intravenous test dose: Historically, a small test dose was recommended before the full dose. Current international guidelines (e.g., UK Royal College of Physicians) state that a test dose does not reliably predict anaphylaxis and is not mandatory; instead, slow administration and full availability of resuscitation equipment are considered the most important safeguards
- Thiamine levels and laboratory monitoring: In patients with renal failure, hepatic dysfunction, or during prolonged parenteral nutrition, thiamine status (e.g., whole blood thiamine diphosphate or erythrocyte transketolase activity) may be assessed, although these tests are not universally available
In any patient with suspected or confirmed thiamine deficiency (including all patients with chronic alcohol use, malnutrition, hyperemesis, or altered consciousness of unknown cause), parenteral thiamine must be administered before any intravenous fluid containing dextrose or glucose. Failure to do so can trigger acute Wernicke's encephalopathy within hours, with potentially irreversible neurological damage. This is one of the most important patient safety principles in emergency and addiction medicine.
Pregnancy and Breastfeeding
Thiamine is a normal dietary constituent and a physiologically essential nutrient throughout pregnancy and lactation. Thiamine requirements are slightly increased during pregnancy (approximately 1.4 mg/day compared to 1.1 mg/day in non-pregnant adults) and during breastfeeding (approximately 1.4 mg/day).
During pregnancy, Thiamine Kabi should be used when clearly indicated. Severe hyperemesis gravidarum causing prolonged vomiting and weight loss is a recognised cause of Wernicke's encephalopathy in pregnancy and is associated with significant maternal morbidity as well as fetal loss if untreated. Parenteral thiamine replacement in this context is considered standard of care and is lifesaving. Standard thiamine supplementation during pregnancy has not been associated with teratogenicity in human or animal studies. Any pregnant patient admitted with persistent vomiting, malnutrition, or altered mental status should be assessed for thiamine deficiency and receive parenteral replacement where indicated.
During breastfeeding, thiamine passes into breast milk, and maternal supplementation is important for the infant's development. There is no evidence that therapeutic doses of parenteral thiamine harm the breastfed infant; rather, untreated maternal deficiency increases the risk of infantile beriberi, a rare but potentially fatal condition in exclusively breastfed infants of thiamine-deficient mothers. Breastfeeding can generally continue during thiamine replacement therapy.
Driving and Operating Machinery
Thiamine itself has no known direct effect on the ability to drive or operate machinery. However, the underlying conditions for which Thiamine Kabi is used (Wernicke's encephalopathy, severe alcohol withdrawal, malnutrition with cognitive impairment) are themselves absolute contraindications to driving or operating dangerous equipment. Patients should not drive or perform safety-critical tasks until their underlying condition has been stabilised and their treating clinician has confirmed that cognitive and motor function are adequate.
Use in Special Populations
Renal impairment: Thiamine is predominantly excreted by the kidneys. Patients with chronic kidney disease or on haemodialysis lose thiamine into the dialysate and are at increased risk of deficiency. No specific dose adjustment is usually required, but monitoring of clinical status and, where available, blood thiamine levels may be helpful.
Hepatic impairment: Chronic liver disease, particularly alcohol-related liver disease, frequently coexists with thiamine deficiency. Thiamine can be used safely in these patients, who often require replacement as part of their overall management.
Elderly patients: Older adults may be at higher risk of unrecognised thiamine deficiency due to reduced food intake, multiple medications, and chronic illness. No specific dose adjustment is required for parenteral thiamine in the elderly, but the underlying risk–benefit and hypersensitivity precautions apply as in all adult patients.
How Does Thiamine Kabi Interact with Other Drugs?
Clinically important interactions with Thiamine Kabi include intravenous dextrose (can precipitate Wernicke's encephalopathy if given before thiamine in deficient patients), loop diuretics (increase renal thiamine loss), 5-fluorouracil (impairs thiamine activation), long-term phenytoin therapy, and certain alkaline intravenous solutions which can inactivate thiamine. Thiamine may also potentiate non-depolarising neuromuscular blocking agents.
Inform the prescribing clinician about all current medications, including prescription drugs, over-the-counter products, herbal supplements, and recent or ongoing chemotherapy. Although thiamine has a generally favourable interaction profile, several clinically relevant interactions influence its effectiveness, safety, or administration.
Major Interactions
| Interacting Agent | Class / Category | Effect | Clinical Significance |
|---|---|---|---|
| Intravenous glucose/dextrose | IV carbohydrate solution | In thiamine-deficient patients, IV glucose consumes remaining thiamine stores in glucose oxidation, potentially precipitating or worsening Wernicke's encephalopathy | Always administer parenteral thiamine before or with IV glucose in at-risk patients |
| 5-Fluorouracil (5-FU) | Antineoplastic (chemotherapy) | Inhibits thiamine phosphorylation to thiamine pyrophosphate, the active coenzyme form; can induce thiamine deficiency even with adequate intake | Monitor for signs of deficiency in prolonged 5-FU therapy; prophylactic thiamine may be considered |
| Loop diuretics (furosemide, bumetanide) | Diuretic | Increase urinary thiamine excretion; long-term high-dose use is associated with thiamine deficiency in heart failure patients | Consider thiamine supplementation in patients on prolonged loop diuretic therapy, especially with heart failure |
| Non-depolarising muscle relaxants | Neuromuscular blocking agent | Thiamine may potentiate the effect of non-depolarising neuromuscular blockers, theoretically prolonging duration of neuromuscular blockade | Monitor train-of-four response during anaesthesia in patients receiving high-dose parenteral thiamine |
| Alkaline IV solutions | Pharmaceutical incompatibility | Thiamine is unstable in alkaline solutions (pH > 8) such as those containing sodium bicarbonate, sulphites, or carbonates; rapidly inactivates | Do not mix Thiamine Kabi with alkaline infusions or citrate-containing fluids; administer in separate lines if necessary |
| Phenytoin (long-term) | Anticonvulsant | Chronic use may reduce blood thiamine concentrations, possibly through enzyme induction and altered metabolism | Consider monitoring thiamine status in long-term phenytoin therapy, particularly in at-risk patients |
Minor Interactions and Pharmaceutical Incompatibilities
| Interacting Agent | Effect | Clinical Significance |
|---|---|---|
| Chronic alcohol consumption | Reduces intestinal absorption, hepatic activation, and storage of thiamine; markedly increases requirement | Alcohol use disorder is a primary indication for prophylactic parenteral thiamine |
| Tea and coffee (caffeine, tannins) | Can impair oral thiamine absorption with heavy chronic intake; negligible effect on parenteral administration | No specific action required for injectable preparations |
| Sulphite-containing IV fluids | Sulphites degrade thiamine rapidly in solution | Avoid mixing Thiamine Kabi with sulphite-preserved fluids |
| Heparin (large doses) | Theoretical thiamine depletion with very long-term high-dose heparin | Rarely clinically relevant in modern practice |
| Neomycin (long-term oral) | May impair intestinal absorption of several B vitamins including thiamine | Consider supplementation during prolonged courses |
Thiamine Kabi may also cause false-positive results in uric acid analysis using the phosphotungstate method and in urobilinogen testing using the Ehrlich reagent. Laboratory staff should be informed when such tests are requested during ongoing thiamine therapy so alternative methods can be used if necessary.
What Is the Correct Dosage of Thiamine Kabi?
Thiamine Kabi 50 mg/ml is dosed according to the severity of deficiency and the indication. For suspected or confirmed Wernicke's encephalopathy, 500 mg is typically given intravenously three times daily for 2–3 days, followed by 250 mg once daily for another 3–5 days. For prophylaxis in high-risk patients (e.g., alcohol withdrawal), 250 mg once daily for 3–5 days is usual. Doses should always be individualised by a qualified clinician.
Always follow the prescription and hospital protocol precisely. Thiamine Kabi is administered exclusively by healthcare professionals, most commonly in emergency departments, acute medical units, and during supervised detoxification. The following dosing regimens are based on international guidelines (UK Royal College of Physicians, EFNS, WHO) and should be adapted to the clinical context.
Adults
Treatment of Wernicke's encephalopathy (confirmed or suspected)
Regimen: 500 mg of thiamine (10 ml of Thiamine Kabi 50 mg/ml) diluted in 100 ml of sodium chloride 0.9% or glucose 5%, administered as an intravenous infusion over at least 30 minutes, three times daily, for 2–3 days.
Maintenance: If a response is observed, continue with 250 mg once daily intravenously or intramuscularly for a further 3–5 days, or until clinical improvement plateaus. Oral thiamine (e.g., 100 mg three times daily) is then usually prescribed long-term.
If no response after 2–3 days: The diagnosis should be reconsidered; consider parallel magnesium replacement, which is frequently co-deficient and necessary for thiamine-dependent enzyme function.
Prophylaxis in high-risk patients (alcohol withdrawal, malnutrition)
Regimen: 250 mg of thiamine (5 ml of Thiamine Kabi 50 mg/ml) intravenously or intramuscularly once daily for 3–5 days, followed by long-term oral thiamine (100 mg three times daily) if risk factors persist.
Indication: Adults undergoing medically supervised alcohol withdrawal, severely malnourished patients, those with hyperemesis gravidarum, patients prior to re-feeding, and following bariatric surgery complicated by persistent vomiting.
Wet beriberi with high-output cardiac failure
Regimen: 100–200 mg of thiamine intravenously once or twice daily, with careful cardiac monitoring, for 5–7 days, then transitioned to oral therapy based on clinical response.
Cardiac improvement is often dramatic within 24–48 hours of parenteral thiamine replacement.
Dry beriberi (peripheral neuropathy)
Regimen: 50–100 mg of thiamine intramuscularly or slowly intravenously once daily for 7–14 days, followed by oral maintenance therapy. Neurological recovery may take weeks to months and is not always complete in long-standing cases.
Children and Adolescents
Paediatric use
Thiamine Kabi is rarely needed in children in developed countries, but can be used when severe deficiency is suspected (for example, in inherited metabolic disorders such as thiamine-responsive megaloblastic anaemia, maple syrup urine disease, or pyruvate dehydrogenase deficiency). Typical doses are 10–50 mg intravenously or intramuscularly once or twice daily, adjusted according to weight and the specific condition. Paediatric dosing should be prescribed by, or in consultation with, a paediatric specialist.
Elderly Patients
Elderly dosage
No specific dose adjustment is required for elderly patients based on age alone. Given the higher prevalence of malnutrition, multiple medications, and chronic illness in older adults, clinicians should have a low threshold for suspecting and treating thiamine deficiency. Standard adult regimens apply, with particular attention to hypersensitivity precautions and slower infusion rates where relevant.
How Thiamine Kabi Is Administered
Thiamine Kabi can be administered by the following routes:
- Intravenous infusion: Dilute the prescribed dose in 100 ml of sodium chloride 0.9% or glucose 5% and infuse over at least 30 minutes. This is the preferred route for high-dose therapy
- Slow intravenous injection: Administer undiluted or partially diluted over at least 10 minutes. Rapid bolus injection is contraindicated due to the risk of hypotension and anaphylactoid reactions
- Deep intramuscular injection: Into a large muscle mass (gluteal or vastus lateralis). Intramuscular administration is particularly useful when intravenous access is difficult or the patient is ambulatory. Injection may be painful and induration at the site is common
Thiamine Kabi should always be administered by trained healthcare professionals in a clinical setting where immediate access to cardiopulmonary resuscitation (CPR), intravenous adrenaline (epinephrine), oxygen, and a trained emergency response team is available. The solution should be inspected before use; any discoloured or visibly particulate solution must be discarded.
Missed Dose
Because Thiamine Kabi is administered in a clinical setting, a missed dose will be managed by the responsible nursing or medical team according to hospital protocol. In general, a missed dose should be given as soon as recognised, and the subsequent dose scheduled to maintain the prescribed frequency. Doses should not be doubled to compensate. Patients transitioning to oral thiamine after discharge should be counselled on the importance of daily adherence.
Overdose
Acute thiamine overdose is extremely rare because excess thiamine is rapidly excreted in the urine. Even very large parenteral doses (up to 1 g or more) have generally been well tolerated in terms of toxicity. The most important concern with “overdose” is in fact the acute hypersensitivity reaction that can occur with rapid intravenous administration of therapeutic doses, not a classic pharmacological overdose.
If a patient develops signs of anaphylaxis during or shortly after thiamine administration (difficulty breathing, wheeze, facial or throat swelling, urticaria, hypotension, loss of consciousness), the infusion must be stopped immediately. Treatment follows standard anaphylaxis protocols: intramuscular adrenaline (epinephrine) 0.5 mg (0.5 ml of 1:1000 in adults), high-flow oxygen, intravenous fluids, and adjunctive antihistamines and corticosteroids. The patient should be monitored in a critical care setting for at least 6–12 hours due to the risk of biphasic anaphylaxis.
What Are the Side Effects of Thiamine Kabi?
Thiamine Kabi is generally well tolerated, but parenteral administration carries a small risk of hypersensitivity reactions including, rarely, anaphylaxis. Common side effects are local reactions at the injection site. Less commonly, transient warmth, sweating, nausea, or mild skin rash may occur. Severe reactions such as bronchospasm, angioedema, and cardiovascular collapse are very rare but require immediate emergency treatment.
As with all medicines, Thiamine Kabi may cause side effects, although not all patients experience them. Most adverse events are mild and transient, related to the injection itself rather than to systemic effects of thiamine. Adverse reactions are classified according to their frequency based on post-marketing experience and clinical studies:
Common
- Injection site reactions – local pain, erythema (redness), warmth, and induration (hardening) at the site of intramuscular or intravenous injection
- Transient warmth or flushing – a feeling of heat or flushing during or immediately after intravenous administration
Uncommon
- Mild gastrointestinal disturbance – nausea, transient abdominal discomfort
- Diaphoresis (sweating) – generalised sweating during or after injection
- Mild skin reactions – localised rash, pruritus (itching), or urticaria
- Palpitations or tachycardia – usually transient and self-limiting
- Dyspnoea (mild shortness of breath) – without overt bronchospasm or anaphylaxis
Rare
- Angioedema – swelling of the face, lips, tongue, or throat
- Bronchospasm – wheezing, shortness of breath, or chest tightness
- Hypotension – a transient drop in blood pressure, particularly with rapid intravenous injection
- Generalised urticaria – widespread hives
- Anaphylactoid reaction – rapid-onset severe systemic allergic reaction
Very rare
- Anaphylaxis – life-threatening allergic reaction with cardiovascular collapse
- Cardiac arrhythmias – in the context of severe anaphylactoid reactions
- Cyanosis and respiratory failure – in the context of severe hypersensitivity
- Death – reported in isolated historical cases, overwhelmingly in the context of rapid IV injection without prompt resuscitation
Difficulty breathing or wheezing, tightness in the chest or throat, swelling of the face, lips, tongue or throat, sudden drop in blood pressure, dizziness or loss of consciousness, fast or irregular heartbeat, widespread hives or severe rash. These may indicate an anaphylactoid or anaphylactic reaction, which is rare but can be fatal without rapid treatment. Anaphylaxis is treated with intramuscular adrenaline (epinephrine), oxygen, fluids, and supportive care.
Injection site reactions are the most frequent adverse events and are typically mild and self-limiting within 24–48 hours. Intramuscular injection is generally more painful than intravenous infusion, and rotation of injection sites is recommended if multiple doses are needed. Transient discomfort and a warm sensation during IV infusion are common and do not indicate hypersensitivity; however, the clinician should always be alert to the possibility of an evolving allergic reaction.
Thiamine itself has no known long-term toxicity at therapeutic doses. It is rapidly cleared from the body by renal excretion, and the risk of cumulative toxicity even with prolonged parenteral therapy is negligible.
Reporting Side Effects
Any suspected adverse reaction should be reported to the treating healthcare professional. Patients and caregivers are also encouraged to report suspected side effects directly to national pharmacovigilance authorities, such as the FDA MedWatch programme in the United States, the MHRA Yellow Card scheme in the United Kingdom, the EMA EudraVigilance system in the European Union, or the equivalent agency in other countries. Spontaneous reporting is essential for continued monitoring of the benefit–risk profile of parenteral thiamine, particularly given the rare but important risk of hypersensitivity.
How Should Thiamine Kabi Be Stored?
Thiamine Kabi ampoules and vials should be stored below 25°C in the original outer carton to protect from light. Do not freeze. Once opened, the solution should be used immediately; any unused portion must be discarded. When diluted for infusion, the product is typically used within 24 hours of preparation, depending on local pharmacy guidelines. Store out of the sight and reach of children.
Correct storage is important to preserve the potency and safety of thiamine, which is sensitive to light, heat, and alkaline conditions. Thiamine Kabi is managed predominantly in pharmacy and hospital settings rather than by patients at home. Standard storage recommendations include:
- Temperature: Store below 25°C. Do not refrigerate unless specifically instructed by the product labelling. Do not freeze; freezing can damage the primary packaging and alter the solution
- Light protection: Keep the ampoules or vials in the outer carton until just before use. Thiamine solutions degrade on prolonged exposure to direct sunlight or strong artificial light
- Single-dose use: Thiamine Kabi is typically supplied in single-dose containers. After opening, the solution should be used immediately. Any unused volume must be discarded in accordance with pharmaceutical waste protocols; partial contents must not be saved for later use
- Dilution and stability: When diluted in sodium chloride 0.9% or glucose 5% for infusion, the prepared solution is generally used within 24 hours and protected from light during storage. Local hospital pharmacy guidelines should be followed precisely
- Visual inspection: Before administration, the solution should be visually inspected. It should be clear and essentially free from visible particulate matter. Any discoloured, cloudy, or precipitate-containing solution must be discarded
- Expiry date: Do not use Thiamine Kabi after the expiry date stated on the ampoule or carton. The expiry date refers to the last day of the indicated month
- Child safety: Store out of the sight and reach of children, ideally in a locked medicines cabinet in pharmacy or ward areas
Unused or expired ampoules must not be disposed of in household waste or wastewater. Pharmaceutical waste must be managed through approved clinical waste streams in accordance with national regulations, to prevent environmental contamination and to reduce the risk of accidental exposure.
What Does Thiamine Kabi Contain?
Each millilitre of Thiamine Kabi contains 50 mg of thiamine hydrochloride (vitamin B1) as the active ingredient. The solution also contains inactive ingredients (excipients) used to stabilise the preparation and adjust its pH for safe parenteral administration. The product does not contain sugars or alcohol.
Active Ingredient
The active substance is thiamine hydrochloride 50 mg per ml, equivalent to 50 mg of vitamin B1 per millilitre of solution. Thiamine hydrochloride is a white, crystalline, water-soluble compound that is converted in the body to thiamine pyrophosphate, the biologically active coenzyme form. The hydrochloride salt is highly stable in acidic aqueous solutions and is the standard form used in parenteral vitamin B1 preparations worldwide.
Inactive Ingredients (Excipients)
Thiamine Kabi solution for injection contains the following excipients in addition to the active ingredient:
- Water for injections – the principal solvent for parenteral solutions
- Sodium hydroxide and/or hydrochloric acid – used to adjust the pH of the solution to a suitable range for parenteral administration (typically between 2.5 and 4.5)
The formulation is free from preservatives, sulphites, lactose, gluten, alcohol, and common allergenic excipients. Always consult the current product information leaflet supplied with the medication for the complete, up-to-date list of excipients, as formulations may be updated over time.
Thiamine Kabi has an acidic pH because thiamine is only stable in acidic solutions. Do not mix the product with alkaline solutions (such as those containing sodium bicarbonate, carbonates, citrates, or sulphites), as this will rapidly inactivate the thiamine and may cause precipitation. When co-administering other medicines, use separate intravenous lines or flush the line with sodium chloride 0.9% between infusions.
Appearance and Packaging
Thiamine Kabi 50 mg/ml is a clear, colourless to slightly yellow-tinted solution for injection. It is supplied in glass ampoules or single-dose vials, typically in pack sizes suitable for hospital use (commonly 1 ml or 2 ml ampoules, packaged in cartons of 10 or more units). Not all pack sizes or presentations may be marketed in every country. The exact presentation details are specified in the current local Summary of Product Characteristics (SmPC) or product leaflet.
The product is authorised by national medicines agencies for prescription hospital use. In countries where Thiamine Kabi is marketed by Fresenius Kabi or equivalent suppliers, the product is typically included in essential medicines lists because of its lifesaving role in the management of Wernicke's encephalopathy and beriberi.
Frequently Asked Questions About Thiamine Kabi
Thiamine Kabi is an injectable form of vitamin B1 (thiamine hydrochloride 50 mg/ml) used to treat and prevent severe thiamine deficiency when oral supplementation is insufficient or unreliable. Its key indications include Wernicke's encephalopathy, Korsakoff syndrome, beriberi (both wet and dry forms), thiamine deficiency related to chronic alcohol use, severe malnutrition, hyperemesis gravidarum, refeeding syndrome, complications after bariatric surgery, and chemotherapy-induced deficiency (particularly from 5-fluorouracil). Treatment is administered by healthcare professionals in a hospital or clinic setting.
In patients with chronic alcohol use or poor nutrition, thiamine body stores are depleted. Glucose metabolism requires thiamine pyrophosphate as an essential cofactor. When intravenous glucose is administered to a thiamine-deficient patient, the sudden surge in glucose metabolism rapidly consumes whatever thiamine remains, particularly in highly metabolic tissues such as the brain. This can precipitate acute Wernicke's encephalopathy within hours, potentially causing permanent neurological damage. International guidelines therefore recommend giving parenteral thiamine before or simultaneously with any glucose-containing intravenous fluid in all patients at risk.
At therapeutic doses, Thiamine Kabi is generally well tolerated. The most common side effects are injection-site reactions (pain, redness, warmth, or induration), and transient sensations of warmth or flushing during intravenous administration. Less common side effects include mild skin rash, itching, sweating, nausea, palpitations, and mild breathlessness. The most important but rare risk is hypersensitivity, including anaphylactoid reactions, angioedema, bronchospasm, and severe hypotension. These are very rare (less than 1 in 10,000 patients) but require immediate emergency treatment with adrenaline and supportive care. Administration should always take place where resuscitation equipment and trained staff are available.
Thiamine Kabi 50 mg/ml is administered by healthcare professionals only. It can be given as a slow intravenous injection (over at least 10 minutes), diluted for intravenous infusion in 100 ml of sodium chloride 0.9% or glucose 5% (over at least 30 minutes), or as a deep intramuscular injection into a large muscle. The dose and route depend on the indication: high-dose IV infusion (500 mg three times daily) is used for Wernicke's encephalopathy, whereas lower doses (typically 250 mg once daily) are used for prophylaxis in high-risk patients such as those undergoing alcohol withdrawal. Rapid IV bolus injection must never be used because of the risk of hypotension and anaphylactoid reactions.
Yes. Thiamine is an essential dietary nutrient, and requirements are slightly increased during pregnancy and breastfeeding. Thiamine Kabi can be safely used during pregnancy when clinically indicated, for example, in women with severe hyperemesis gravidarum who are at risk of Wernicke's encephalopathy. Untreated maternal thiamine deficiency is more dangerous than thiamine replacement itself and can lead to serious maternal and fetal complications. Therapeutic parenteral thiamine has not been associated with teratogenicity in human studies. Breastfeeding can usually continue during treatment, as thiamine passes into breast milk in small amounts that are beneficial rather than harmful to the infant.
Thiamine Kabi must not be given to patients with a known severe hypersensitivity to thiamine or to any excipient in the product, especially those who have previously had a severe anaphylactic reaction to parenteral thiamine. Patients with a history of atopy, asthma, or multiple drug allergies are at slightly higher risk of hypersensitivity and require extra caution during administration. In mild deficiency states where the gut is functioning normally, oral thiamine supplementation is usually preferred to injectable thiamine. Decisions about whether to use Thiamine Kabi must always be made by a qualified healthcare professional who can weigh the benefits against the potential risks.
In many patients, eye movement abnormalities (such as nystagmus and ophthalmoplegia) begin to improve within hours of the first parenteral dose of high-dose thiamine, sometimes dramatically. Ataxia and confusion typically respond more slowly, over days to weeks, and recovery is frequently incomplete if treatment is delayed. This rapid potential for reversal highlights the urgency of giving parenteral thiamine as soon as Wernicke's encephalopathy is suspected, without waiting for laboratory confirmation. In wet beriberi with heart failure, clinical improvement in cardiac function is often evident within 24–48 hours of parenteral thiamine replacement.
References
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Editorial Team
This article has been written and reviewed by qualified medical professionals following international clinical guidelines and the GRADE evidence framework.
iMedic Medical Editorial Team
Licensed physicians with specializations in clinical pharmacology, neurology, emergency medicine, and addiction medicine. All content is based on peer-reviewed research and international guidelines from WHO, EMA, FDA, NICE, EFNS, and the Royal College of Physicians.
iMedic Medical Review Board
Independent panel of board-certified medical specialists who review all content for accuracy, completeness, and adherence to current evidence-based practice guidelines. Conflicts of interest: none declared.