Hydroxyzine Bluefish AB
First-generation antihistamine — H1 receptor antagonist with anxiolytic and sedative properties
Quick facts about Hydroxyzine Bluefish AB
Key Takeaways About Hydroxyzine Bluefish AB
- Dual action: Hydroxyzine acts as both an antihistamine and an anxiolytic, making it useful for anxiety-related itching and allergic conditions
- Non-addictive alternative: Unlike benzodiazepines, hydroxyzine does not carry a risk of physical dependence or abuse, making it a safer option for short-term anxiety management
- Significant drowsiness: Hydroxyzine causes substantial sedation — do not drive, operate machinery, or consume alcohol while taking this medication
- Heart safety concern: Higher doses may prolong the QT interval on ECG; the EMA recommends using the lowest effective dose, especially in elderly patients
- Cetirizine connection: The body converts hydroxyzine into cetirizine (Zyrtec), a well-known second-generation antihistamine, which contributes to its antiallergic effects
What Is Hydroxyzine Bluefish AB and What Is It Used For?
Hydroxyzine Bluefish AB is a first-generation antihistamine containing hydroxyzine hydrochloride 10 mg. It is prescribed for the short-term relief of anxiety, management of pruritus (itching) associated with allergic conditions such as urticaria, and as a sedative before medical procedures.
Hydroxyzine belongs to the piperazine class of antihistamines and was first synthesized in 1956. It has been used clinically for over six decades, making it one of the most well-established antihistamines in medical practice. The drug works primarily by competitively blocking histamine H1 receptors, which are responsible for mediating allergic reactions, but it also crosses the blood-brain barrier readily, producing significant central nervous system effects including sedation and anxiety reduction.
The anxiolytic properties of hydroxyzine are distinct from those of benzodiazepines. While benzodiazepines act on GABA receptors and carry risks of dependence and withdrawal, hydroxyzine achieves its calming effect through H1 receptor blockade and serotonin 5-HT2A receptor antagonism in the central nervous system. This mechanism makes hydroxyzine particularly valuable as a non-addictive option for patients with anxiety who may be at risk of substance dependence, or when benzodiazepines are contraindicated.
In clinical practice, hydroxyzine is used across several therapeutic areas. Its antipruritic (anti-itch) effect is valuable in managing chronic urticaria (hives), atopic dermatitis, and contact dermatitis. The sedative properties make it useful for pre-operative and pre-procedural sedation, particularly in patients undergoing dental procedures, minor surgery, or diagnostic imaging. In some clinical settings, it is used as an adjunct to analgesics to reduce opioid requirements and manage postoperative nausea.
Hydroxyzine Bluefish AB is manufactured by Bluefish Pharmaceuticals AB as a generic formulation bioequivalent to the original branded product. The 10 mg film-coated tablet formulation allows for flexible dosing, which is particularly important given the EMA's 2015 recommendation to use the lowest effective dose due to cardiac safety considerations. Other brands of hydroxyzine include Atarax and Vistaril, though the active substance and clinical effects are identical across all approved formulations.
After oral administration, hydroxyzine is rapidly absorbed from the gastrointestinal tract, with peak plasma concentrations reached within approximately 2 hours. It is extensively metabolized in the liver, primarily by the CYP3A4 enzyme system, into its principal active metabolite cetirizine — which is itself a widely used second-generation antihistamine (marketed as Zyrtec). The elimination half-life of hydroxyzine is approximately 14 hours in adults but can be significantly longer in elderly patients (up to 29 hours), which is why dose adjustments are necessary in this population.
What Should You Know Before Taking Hydroxyzine Bluefish AB?
Before taking hydroxyzine, inform your doctor about any heart conditions, liver or kidney disease, seizure disorders, glaucoma, prostate problems, or if you are pregnant or breastfeeding. Hydroxyzine is contraindicated in patients with known QT prolongation and porphyria.
Contraindications
Hydroxyzine must not be used in certain situations where the risks clearly outweigh any potential benefits. Understanding these contraindications is essential for safe use of the medication.
- Known hypersensitivity to hydroxyzine, cetirizine, other piperazine derivatives, or any of the excipients in the formulation
- Porphyria — hydroxyzine may trigger or worsen acute porphyria attacks
- Known QT interval prolongation — hydroxyzine can further prolong the QT interval, increasing the risk of potentially fatal cardiac arrhythmias
- Pregnancy — hydroxyzine is contraindicated during pregnancy due to potential fetal harm; animal studies have shown teratogenic effects
- Early pregnancy — particularly in the first trimester, hydroxyzine poses the greatest risk to fetal development
Warnings and Precautions
Several conditions require careful consideration and potentially dose adjustments or enhanced monitoring when using hydroxyzine. Discuss all of the following with your healthcare provider before starting treatment.
Cardiac effects: In 2015, the European Medicines Agency (EMA) issued a safety review concluding that hydroxyzine carries a small but clinically significant risk of QT interval prolongation and torsades de pointes, particularly at higher doses. As a result, the EMA recommended restricting the maximum daily dose to 100 mg in adults (50 mg in elderly patients), using the lowest effective dose, and avoiding hydroxyzine in patients with known risk factors for QT prolongation including electrolyte imbalances (particularly hypokalemia and hypomagnesemia), pre-existing cardiovascular disease, family history of sudden cardiac death, and concurrent use of other QT-prolonging medications.
Hepatic impairment: Since hydroxyzine is extensively metabolized by the liver, patients with hepatic insufficiency may experience significantly increased drug exposure. Dose reduction by approximately 33% is recommended in patients with mild-to-moderate liver disease, and hydroxyzine should be used with extreme caution or avoided entirely in severe hepatic impairment.
Renal impairment: Although hydroxyzine itself is not primarily renally eliminated, its active metabolite cetirizine is excreted by the kidneys. In patients with moderate-to-severe renal impairment, cetirizine accumulation can occur, prolonging and intensifying both therapeutic and adverse effects. Dose reduction is recommended.
Elderly patients: Older adults are more susceptible to the anticholinergic and sedative effects of hydroxyzine. They are at increased risk of falls, cognitive impairment, urinary retention, and constipation. The Beers Criteria, published by the American Geriatrics Society, lists hydroxyzine as a potentially inappropriate medication for elderly patients. When hydroxyzine must be used in this population, the maximum daily dose should not exceed 50 mg.
Seizure disorders: Hydroxyzine may lower the seizure threshold in susceptible individuals. Patients with epilepsy or a history of seizures should use hydroxyzine with caution and under close medical supervision.
Hydroxyzine has been associated with QT interval prolongation and potentially fatal heart rhythm disturbances (torsades de pointes). Use the lowest effective dose for the shortest possible duration. Seek immediate medical attention if you experience palpitations, fainting, dizziness, or irregular heartbeat while taking this medication. Do not exceed the recommended maximum dose.
Pregnancy and Breastfeeding
Hydroxyzine is contraindicated during pregnancy. Animal reproduction studies have demonstrated adverse fetal effects including cleft palate and other skeletal abnormalities at doses relevant to human use. Although controlled studies in pregnant women are limited, the available evidence is sufficient to warrant avoidance of hydroxyzine throughout pregnancy. Neonates exposed to hydroxyzine in late pregnancy may experience withdrawal symptoms or adverse effects including hypotonia, movement disorders, and sedation.
Hydroxyzine and its metabolite cetirizine are excreted in breast milk. Because of the potential for adverse effects in breastfed infants — including sedation, irritability, and anticholinergic effects — hydroxyzine should not be used during breastfeeding. If antihistamine therapy is required during lactation, second-generation antihistamines such as cetirizine or loratadine are generally preferred due to lower levels of sedation and better safety profiles in nursing infants.
How Does Hydroxyzine Bluefish AB Interact with Other Drugs?
Hydroxyzine interacts significantly with CNS depressants (alcohol, opioids, benzodiazepines), QT-prolonging drugs, anticholinergic medications, and CYP3A4 inhibitors. These interactions can enhance sedation, increase cardiac risk, or alter hydroxyzine's metabolism.
Drug interactions with hydroxyzine are clinically important because they can significantly amplify its sedative, anticholinergic, and cardiac effects. Hydroxyzine is metabolized primarily by the hepatic cytochrome P450 enzyme CYP3A4 and to a lesser extent by CYP3A5, which means that drugs affecting these enzyme pathways can alter hydroxyzine plasma levels. Additionally, its pharmacodynamic profile creates interactions with any drug that shares its sedative, anticholinergic, or cardiac effects.
Major Interactions
| Interacting Drug/Class | Effect | Clinical Significance |
|---|---|---|
| Alcohol | Synergistic CNS depression; additive sedation, impaired cognition and motor function | Avoid completely. Can cause severe sedation, respiratory depression, and increased accident risk |
| Opioid analgesics (morphine, codeine, tramadol, fentanyl) | Enhanced sedation, respiratory depression, and hypotension | Dose reduction of opioid may be required. Monitor respiratory function closely |
| Benzodiazepines (diazepam, alprazolam, lorazepam) | Additive CNS depression and sedation | Avoid combination when possible. If necessary, use lowest doses with close monitoring |
| QT-prolonging drugs (erythromycin, haloperidol, amiodarone, citalopram) | Additive QT prolongation increasing risk of torsades de pointes | Contraindicated combination. Risk of fatal cardiac arrhythmias |
| MAO inhibitors (phenelzine, tranylcypromine) | Enhanced and prolonged anticholinergic effects | Avoid concurrent use. Wait at least 14 days after stopping an MAOI |
| CYP3A4 inhibitors (ketoconazole, itraconazole, clarithromycin) | Increased hydroxyzine plasma levels due to inhibited metabolism | Dose reduction of hydroxyzine may be required. Monitor for increased sedation and adverse effects |
Minor Interactions
| Interacting Drug/Class | Effect | Clinical Significance |
|---|---|---|
| Anticholinergic drugs (amitriptyline, oxybutynin, ipratropium) | Additive anticholinergic effects: dry mouth, urinary retention, constipation, confusion | Monitor for anticholinergic burden, especially in elderly patients |
| Anticonvulsants (phenytoin, carbamazepine) | CYP3A4 inducers may reduce hydroxyzine levels; additive sedation possible | Monitor therapeutic effect. Dose adjustment may be needed |
| Antihypertensives (beta-blockers, ACE inhibitors) | Additive hypotensive effect | Monitor blood pressure, especially when initiating therapy |
| Acetylcholinesterase inhibitors (donepezil, rivastigmine) | Hydroxyzine's anticholinergic properties may antagonize therapeutic effect | Avoid in patients being treated for dementia |
Hydroxyzine may interfere with certain diagnostic tests. It can suppress the wheal-and-flare response in allergy skin testing, producing false-negative results. Patients should discontinue hydroxyzine at least 5 days before scheduled allergy skin prick tests. Additionally, hydroxyzine can interfere with urine corticosteroid determinations (17-hydroxycorticosteroids), potentially affecting the diagnosis of adrenal disorders.
What Is the Correct Dosage of Hydroxyzine Bluefish AB?
The typical adult dose of hydroxyzine is 25–50 mg taken 2–3 times daily for anxiety, or 25 mg at bedtime for pruritus. The maximum recommended daily dose is 100 mg for adults and 50 mg for elderly patients, following EMA safety guidelines issued in 2015.
Dosing of hydroxyzine should always follow the principle of using the lowest effective dose for the shortest necessary duration. This is particularly important given the EMA's 2015 safety review, which linked higher doses to QT prolongation risk. All doses should be individualized based on the patient's age, weight, clinical condition, and response to treatment.
Adults
Anxiety
Initial dose: 25–50 mg taken 3–4 times daily. Maximum daily dose: 100 mg. Treatment should be limited to the shortest possible duration. For acute anxiety states, a single dose of 50–100 mg may be given as needed. Hydroxyzine is intended for short-term use (typically less than 4 weeks) and should not replace longer-term psychological or pharmacological treatments for anxiety disorders.
Pruritus (Itching)
Initial dose: 25 mg at bedtime, increasing to 25 mg three times daily if needed. Maximum daily dose: 100 mg. The bedtime dose takes advantage of hydroxyzine's sedative effect to reduce nighttime itching and improve sleep quality. For chronic urticaria, second-generation antihistamines are generally preferred as first-line therapy due to fewer sedative side effects.
Pre-operative Sedation
50–100 mg given as a single dose approximately 1 hour before the procedure. This helps reduce anxiety and can complement general anesthesia or sedation. The dose should be adjusted based on the patient's overall anesthetic plan and other sedating medications being used.
Children
Children over 6 years of age
For pruritus and anxiety: 1 mg/kg/day in divided doses, up to a maximum of 2 mg/kg/day. Hydroxyzine should be used with caution in children and for the shortest possible duration. The EMA recommends a maximum daily dose of 2 mg/kg in children weighing up to 40 kg. For children weighing over 40 kg, the adult dose applies but the maximum should not exceed 100 mg per day.
Children under 6 years
Use of hydroxyzine in children under 6 years of age is generally not recommended due to limited safety data in this age group. If clinically necessary, the dose should be carefully calculated by the prescribing physician based on the child's weight.
Elderly Patients
Dose recommendations for patients over 65 years
Start at half the standard adult dose (12.5 mg). Maximum daily dose: 50 mg. Elderly patients are more susceptible to the sedative, anticholinergic, and cardiac effects of hydroxyzine. The prolonged half-life in older adults (up to 29 hours compared to 14 hours in younger adults) means that drug accumulation is more likely, increasing the risk of adverse effects including falls, confusion, urinary retention, and QT prolongation. The American Geriatrics Society Beers Criteria recommends avoiding hydroxyzine in elderly patients when possible.
Missed Dose
If you miss a dose of hydroxyzine, take it as soon as you remember. However, if it is nearly time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one, as this increases the risk of excessive sedation and adverse effects. If hydroxyzine is being used on an as-needed basis, simply take the next dose when it is required.
Overdose
If you suspect an overdose of hydroxyzine, seek emergency medical help immediately by calling your local emergency number or poison control center. Symptoms of hydroxyzine overdose include profound sedation, nausea, vomiting, involuntary motor activity, hypotension, respiratory depression, cardiac conduction disturbances (QT prolongation, torsades de pointes), and in severe cases, seizures and coma. Treatment is supportive and symptomatic; there is no specific antidote. Gastric lavage may be considered if the patient presents within 1 hour of ingestion. Continuous cardiac monitoring is essential to detect QT prolongation and arrhythmias.
What Are the Side Effects of Hydroxyzine Bluefish AB?
The most common side effects of hydroxyzine are drowsiness, dry mouth, headache, and fatigue. More serious but rare side effects include QT prolongation, seizures, and severe allergic reactions. Most side effects are dose-dependent and reversible upon dose reduction or discontinuation.
Like all medications, hydroxyzine can cause side effects, although not everyone experiences them. The most frequently reported adverse effects are related to its antihistaminic and anticholinergic properties. Drowsiness is the most common side effect and is often the most clinically significant, particularly at the beginning of treatment. Most side effects are dose-dependent, meaning they are more likely to occur and more severe at higher doses. Tolerance to the sedative effect often develops within the first few days of regular use.
The following classification uses the standard frequency categories established by the Council for International Organizations of Medical Sciences (CIOMS): Very Common (≥1/10), Common (≥1/100 to <1/10), Uncommon (≥1/1,000 to <1/100), Rare (<1/1,000).
Very Common (>1/10)
- Drowsiness and somnolence
- Sedation
- Headache
Common (1/10 – 1/100)
- Dry mouth (xerostomia)
- Fatigue and malaise
- Dizziness
- Insomnia (paradoxical reaction)
- Nausea
- Constipation
- Blurred vision
Uncommon (1/100 – 1/1,000)
- Tachycardia (rapid heartbeat)
- Urinary retention
- Tremor
- Agitation or restlessness (paradoxical effect, more common in children and elderly)
- Skin rash or urticaria
- Confusion
- Hypotension
Rare (<1/1,000)
- QT interval prolongation and cardiac arrhythmias (including torsades de pointes)
- Seizures (particularly in predisposed patients)
- Severe allergic reactions (anaphylaxis, angioedema)
- Hepatic dysfunction (elevated liver enzymes)
- Bronchospasm
- Dyskinesia and involuntary movements
- Fixed drug eruption
If you experience any side effects, including those not listed above, speak to your doctor or pharmacist. You can also report side effects directly to your national pharmacovigilance authority. By reporting side effects, you help provide more information on the safety of this medicine.
Drowsiness: Take the majority of your daily dose at bedtime. Tolerance usually develops within a few days. Dry mouth: Sip water frequently, chew sugar-free gum, or use saliva substitutes. Constipation: Increase dietary fiber and fluid intake. Dizziness: Rise slowly from sitting or lying positions. If drowsiness persists and interferes with daily activities, discuss dose adjustment with your doctor.
How Should You Store Hydroxyzine Bluefish AB?
Store hydroxyzine at room temperature below 25°C (77°F), in the original packaging, protected from light and moisture. Keep out of reach and sight of children.
Proper storage of hydroxyzine is essential to maintain its effectiveness and safety throughout its shelf life. Film-coated tablets should be stored in their original blister packaging until use to protect them from moisture degradation. The tablets should not be stored in the bathroom or near the kitchen sink, where moisture and temperature fluctuations are common.
Key storage guidelines:
- Temperature: Store below 25°C (77°F). Do not freeze. Brief exposures to temperatures up to 30°C are generally tolerable but should be minimized
- Light protection: Keep in the original packaging to protect from light, which can degrade the active substance
- Moisture: Store in a dry place. Do not remove tablets from the blister pack until you are ready to take them
- Child safety: Store in a secure location out of reach and sight of children. Accidental ingestion by children can cause serious adverse effects
- Expiry date: Do not use the tablets after the expiry date stated on the packaging. The expiry date refers to the last day of that month
- Disposal: Do not dispose of unused tablets in household waste or flush them down the toilet. Return unused medication to your pharmacy for proper disposal according to local regulations
What Does Hydroxyzine Bluefish AB Contain?
Each film-coated tablet contains 10 mg of hydroxyzine hydrochloride as the active substance, along with standard pharmaceutical excipients including lactose monohydrate, microcrystalline cellulose, and a film-coating.
Understanding the full composition of Hydroxyzine Bluefish AB is important for patients with known allergies or intolerances to specific pharmaceutical ingredients. The film-coated tablet formulation is designed for oral administration with consistent drug release and stability.
Active substance: Each tablet contains hydroxyzine hydrochloride 10 mg, equivalent to approximately 8.5 mg of hydroxyzine base. Hydroxyzine hydrochloride is a white, odorless powder that is highly soluble in water, which facilitates rapid absorption from the gastrointestinal tract.
Excipients (inactive ingredients):
- Tablet core: Lactose monohydrate, microcrystalline cellulose, colloidal anhydrous silica, magnesium stearate, and croscarmellose sodium (as a disintegrant to facilitate tablet breakdown)
- Film coating: Hypromellose (hydroxypropyl methylcellulose), titanium dioxide (E171), and macrogol (polyethylene glycol) — these provide the protective coating, improve swallowability, and give the tablet its appearance
Hydroxyzine Bluefish AB tablets contain lactose monohydrate. Patients with rare hereditary galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption should not take this medicine. If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicine.
Frequently Asked Questions About Hydroxyzine Bluefish AB
Hydroxyzine Bluefish AB is a first-generation antihistamine prescribed for the short-term management of anxiety, treatment of pruritus (itching) associated with allergic conditions such as urticaria and dermatitis, and as a pre-operative sedative. It works by blocking H1 histamine receptors and has additional anticholinergic and sedative properties. Unlike benzodiazepines, it does not carry a risk of physical dependence.
Hydroxyzine is rapidly absorbed after oral administration and typically begins to take effect within 15 to 30 minutes. Peak plasma concentrations are reached approximately 2 hours after ingestion, and the clinical effects can last 4 to 6 hours. The sedative effect is usually the first to be noticed, while the full anxiolytic and antipruritic effects may take slightly longer to manifest.
No, hydroxyzine is not considered addictive and does not carry the same risk of physical dependence as benzodiazepines. It does not act on GABA receptors and has no known abuse potential. However, it should still be used for the shortest possible duration, particularly for anxiety, and should not be stopped abruptly after prolonged use without consulting a healthcare provider, as some patients may experience rebound symptoms.
No, alcohol should be strictly avoided while taking hydroxyzine. Both substances are central nervous system depressants, and their combined use can lead to excessive sedation, impaired motor function, respiratory depression, and significantly reduced alertness. This combination increases the risk of accidents, injuries, and potentially dangerous respiratory depression.
Cetirizine (marketed as Zyrtec) is actually an active metabolite of hydroxyzine — your body converts hydroxyzine into cetirizine during metabolism. The key difference is that cetirizine is a second-generation antihistamine that does not significantly cross the blood-brain barrier, meaning it causes much less drowsiness. Hydroxyzine crosses the blood-brain barrier freely, which gives it sedative and anxiolytic properties but also causes more drowsiness. Cetirizine is used primarily for allergies, while hydroxyzine is also used for anxiety and as a sedative.
At higher doses, hydroxyzine has been associated with QT interval prolongation on ECG, which can potentially lead to serious heart rhythm disturbances including torsades de pointes. The EMA issued safety warnings in 2015 recommending dose restrictions, particularly in elderly patients. Hydroxyzine should be used at the lowest effective dose and avoided in patients with pre-existing QT prolongation, significant electrolyte imbalances, or those taking other QT-prolonging medications. If you experience palpitations, fainting, or irregular heartbeat, seek medical attention immediately.
References
- European Medicines Agency (EMA). (2015). PRAC recommends new measures to minimise known heart risks of hydroxyzine-containing medicines. EMA/144823/2015. Available at: ema.europa.eu
- World Health Organization. (2023). WHO Model List of Essential Medicines – 23rd list. Geneva: World Health Organization. Available at: who.int
- Simons FER, Simons KJ. (2011). Histamine and H1-antihistamines: celebrating a century of progress. Journal of Allergy and Clinical Immunology, 128(6), 1139-1150.e4. DOI: 10.1016/j.jaci.2011.09.005
- Guaiana G, Barbui C, Cipriani A. (2010). Hydroxyzine for generalised anxiety disorder. Cochrane Database of Systematic Reviews, Issue 12, Art. No.: CD006815. DOI: 10.1002/14651858.CD006815.pub2
- American Geriatrics Society. (2023). Updated AGS Beers Criteria for Potentially Inappropriate Medication Use in Older Adults. Journal of the American Geriatrics Society, 71(7), 2052-2081. DOI: 10.1111/jgs.18372
- British National Formulary (BNF). (2026). Hydroxyzine hydrochloride monograph. National Institute for Health and Care Excellence (NICE). Available at: bnf.nice.org.uk
- Llorca PM, Spadone C, Sol O, et al. (2002). Efficacy and safety of hydroxyzine in the treatment of generalized anxiety disorder: a 3-month double-blind study. Journal of Clinical Psychiatry, 63(11), 1020-1027. DOI: 10.4088/JCP.v63n1112
- Zuberbier T, Abdul Latiff AH, Abuzakouk M, et al. (2022). The international EAACI/GA2LEN/EuroGuiDerm/APAAACI guideline for the definition, classification, diagnosis, and management of urticaria. Allergy, 77(3), 734-766. DOI: 10.1111/all.15090
Editorial Team
This article has been written and medically reviewed by the iMedic Medical Editorial Team, consisting of licensed physicians specializing in clinical pharmacology, internal medicine, and dermatology. Our team follows international medical guidelines from the WHO, EMA, FDA, BNF, and NICE to ensure all information is accurate, evidence-based, and up to date.
All pharmaceutical content undergoes a rigorous three-step review process: (1) Initial draft by a clinical pharmacology specialist, (2) Peer review by an independent physician, and (3) Final verification against current SmPC data and international guidelines. Content is reviewed and updated at least annually or whenever significant new safety information becomes available.
We use the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) framework to assess the quality of evidence. This article is based on Level 1A evidence from systematic reviews, meta-analyses of randomized controlled trials, official SmPC data, and authoritative clinical guidelines from the EMA, BNF, and WHO.
Conflict of interest declaration: The iMedic Medical Editorial Team has no financial relationships with pharmaceutical companies. All content is independently produced without commercial sponsorship or advertising influence. Read our full editorial standards.