Dormirax

Each Dormirax tablet contains Hydroxyzine diHCl 10 mg or 25 mg.

Each mL of Dormirax syrup contains hydrozyxine diHCl 2 mg.

For symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested.

Useful in the management of pruritus due to allergic conditions such as chronic urticaria and atopic and contact dermatoses, and in histamine-mediated pruritus.

As a sedative when used as premedication and following general anesthesia, Dormirax may potentiate meperidine (Demerol®) and barbiturates, so their use in pre-anesthetic adjunctive therapy should be modified on an individual basis. Atropine and other belladonna alkaloids are not affected by the drug. Dormirax is not known to interfere with the action of digitalis in any way and it may be used concurrently with this agent.

The effectiveness of Dormirax as an antianxiety agent for long-term use, that is, more than 4 months, has not been assessed by systematic clinical studies. The physician should reassess periodically the usefulness of the drug for the individual patient.

Dormirax injection is used to used to help control anxiety and tension caused by dental, nervous, and emotional conditions. It can also be used to help control anxiety and produce sleep before and after surgery. Dormirax is also used to relieve symptoms of an allergic reaction (eg, hives, itching skin) caused by asthma and chronic urticaria.

Dormirax is an antihistamine. It works by preventing the effects of a substance called histamine, which is produced by the body. Dormirax is also used to control anxiety withdrawal symptoms in alcoholic patients. It is also used to control nausea and vomiting symptoms, and relieve anxiety in patients with certain heart disease.

Dormirax is to be given by or under the supervision of your doctor.

For symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested: in adults, 50-100 mg q.i.d.; children under 6 years, 50 mg daily in divided doses; and over 6 years, 50-100 mg daily in divided doses.

For use in the management of pruritus due to allergic conditions such as chronic urticaria and atopic and contact dermatoses, and in histamine-mediated pruritus: in adults, 25 mg t.i.d. or q.i.d.; children under 6 years, 50 mg daily in divided doses; and over 6 years, 50-100 mg daily in divided doses.

As a sedative when used as a premedication and following general anesthesia: 50-100 mg in adults, and 0.6 mg/kg in children.

When treatment is initiated by the intramuscular route of administration, subsequent doses may be administered orally.

As with all medications, the dosage should be adjusted according to the patient's response to therapy.

How supplied

Dormirax® Capsules (Dormirax pamoate equivalent to Dormirax hydrochloride)

25 mg: 100's (NDC 0069-5410-66), two-tone green capsules

50 mg: 100's (NDC 0069-5420-66), green and white capsules

Dormirax®

Oral Suspension (Dormirax pamoate equivalent to 25 mg Dormirax hydrochloride per teaspoonful-5 mL): 1 pint (473 mL) bottles (NDC 0069-5440-93) and 4 ounce (120 mL) bottles (NDC 0069-5440-97) in packages of 4.

Shake vigorously until product is completely resuspended.

BIBLIOGRAPHY - Available on request.

Distributed by: Pfizer Labs Division of Pfizer Inc, NY, NY 10017. Revised: Nov 2016

See also:
What is the most important information I should know about Dormirax?

Hypersensitivity to Dormirax or any of the excipients of Dormirax, to cetirizine, to other piperazine derivatives, to aminophylline, or to ethylenediamine; porphyria; acquired or congenital QT interval prolongation, risk factor to QT interval prolongation including known cardiovascular disease, significant electrolyte imbalance (hypokalemia and hypomagnesemia), family history of sudden cardiac death, significant bradycardia, concomitant use with drugs known to prolong the QT interval and/or induce Torsades de pointes.

Use in pregnancy: Dormirax is contraindicated during pregnancy.

Animal studies have shown reproductive toxicity.

Dormirax crosses the placental barrier leading to higher foetal than maternal concentrations.

To date, no relevant epidemiological data are available relating to exposure to Dormirax during pregnancy.

In neonates whose mothers received Dormirax during late pregnancy and/or labour, the following events were observed immediately or only a few hours after birth: Hypotonia, movement disorders including extrapyramidal disorders, clonic movements, CNS depression, neonatal hypoxic conditions or urinary retention.

Use in lactation: Dormirax is contraindicated during lactation. Breastfeeding should be stopped if Dormirax therapy is needed.

Cetirizine, the principal metabolite of Dormirax, is excreted in human milk.

Although no formal studies have been performed on the excretion of Dormirax in human milk, severe adverse effects have been shown in breastfed newborns/infants of Dormirax treated mothers.

Use Dormirax as directed by your doctor. Check the label on the medicine for exact dosing instructions.

• Dormirax is usually given as an injection at your doctor's office, hospital, or clinic. If you will be using Dormirax at home, a health care provider will teach you how to use it. Be sure you understand how to use Dormirax. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.
• Do not use Dormirax if it contains particles, is cloudy or discolored, or if the vial is cracked or damaged.
• Keep this product, as well as syringes and needles, out of the reach of children and pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.
• If you miss a dose of Dormirax and you are using it regularly, take it as soon as possible. If it is almost time for you next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Dormirax.

Dormirax is used for the short-term treatment of nervousness and tension that may occur with certain mental/mood disorders (e.g., anxiety, dementia). It is also used to help manage withdrawal symptoms (e.g., anxiety, agitation) in alcoholics. Other uses include helping to decrease anxiety and nausea before/after surgery or during childbirth or helping certain narcotic pain relievers (e.g., meperidine) work better.

Dormirax belongs to a class of medications called antihistamines. It is thought to work by affecting certain natural substances (acetylcholine, serotonin) in your body or by acting directly on certain parts of the brain. Dormirax also blocks a natural substance that your body makes during an allergic reaction (histamine).

How to use Dormirax intramuscular

This medication is given by injection into a muscle as directed by your doctor. Dosage is based on your age, weight, medical condition, and response to treatment.

If you are giving this medication to yourself at home, learn all preparation and usage instructions from your health care professional. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.

See also:
What other drugs will affect Dormirax?

Central Nervous System Depressants: Patients should be informed that Dormirax may potentiate the effects of barbiturates, other CNS depressants or drugs having anticholinergic properties.

Alcohol: Alcohol also potentiates the effects of Dormirax.

Betahistine and Anticholinesterase Drugs: Dormirax antagonizes the effects of betahistine and anticholinesterase drugs.

Tests Results: The treatment should be stopped at least 5 days before allergy testing or methacholine bronchial challenge, to avoid effects on the test results.

Monoamine Oxidase Inhibitors: Simultaneous administration of Dormirax with MAOIs should be avoided.

Epinephrine: Dormirax counteracts the epinephrine pressor action.

Phenytoin: In rats, Dormirax antagonized the anticonvulsant action of phenytoin.

Cimetidine: Cimetidine 600 mg twice daily has been shown to increase the serum concentrations of Dormirax by 36% and to decrease peak concentrations of the metabolite cetirizine by 20%.

CYP2D6 Substrates: Dormirax is an inhibitor of cytochrome P-450 2D6 (Ki: 3.9 micrometer; 1.7 mcg/mL) and may cause at high doses drug-drug interactions with CYP2D6 substrates.

Effect on Other Drug Metabolism: Dormirax has no inhibitory effect at 100 micrometer on UDP-glucuronyl transferase isoforms 1A1 and 1A6 in human liver microsomes. It inhibits cytochrome P-450 2C9/C10, 2C19 and 3A4 isoforms at concentrations (IC₅₀: 19-140 micrometer; 7-52 mcg/mL) well above peak plasma concentrations. The metabolite cetirizine at 100 micrometer has no inhibitory effect on human liver cytochrome P-450 (1A2, 2A6, 2C9/C10, 2C19, 2D6, 2E1 and 3A4) and UDP-glucuronyl transferase isoforms. Therefore, Dormirax is unlikely to impair the metabolism of drugs which are substrates for these enzymes.

Potent Inhibitors of Liver Enzymes: As Dormirax is metabolized in the liver, an increase in Dormirax blood concentrations may be expected when Dormirax is co-administered with other drugs known to be potent inhibitors of liver enzymes.

Potentially Arrhythmogenic Drugs: Co-administration of Dormirax with a potentially arrhythmogenic drug may increase the risk of QT prolongation and Torsades de pointes.

See also:
What are the possible side effects of Dormirax?

Adverse effects are mainly related to CNS depressant or paradoxical CNS stimulation effects, to anticholinergic activity, or to hypersensitivity reactions.

Adverse reactions are ranked under headings of frequency using the following convention: Very common ≥1/10, common ≥1/100 to <1/10, uncommon ≥1/1,000 to <1/100, rare ≥1/10,000 to <1/1,000, very rare <1/10,000, not known (cannot be estimated from the available data).

Clinical Trial Data: The following adverse effects were reported in placebo-controlled clinical trials for Dormirax and including 735 subjects exposed to Dormirax up to 50 mg daily.

Nervous System Disorders: Very Common: Somnolence. Common: Headache. Uncommon: Dizziness, insomnia, attention disturbance.

Gastrointestinal Disorders: Common: Dry mouth. Uncommon: Constipation, nausea.

General Disorders and Administration Site Conditions: Common: Fatigue. Uncommon: Asthenia.

Post-Marketing Data: Immune System Disorders: Not Known: Hypersensitivity, anaphylactic shock.

Psychiatric Disorders: Not Known: Agitation, confusion, disorientation, hallucination.

Nervous System Disorders: Not Known: Sedation, tremor, convulsions, dyskinesia.

Eye Disorders: Not Known: Accommodation disorder, blurred vision.

Cardiac Disorders: Not Known: Tachycardia, prolonged electrocardiogram QT, Torsades de pointes.

Vascular Disorders: Not Known: Hypotension.

Respiratory, Thoracic and Mediastinal Disorders: Not Known: Bronchospasm.

Gastrointestinal Disorders: Not Known: Vomiting.

Hepatobiliary Disorders: Not Known: Abnormal liver function tests.

Skin and Subcutaneous Tissue Disorders: Not Known: Pruritus, erythematous rash, maculopapular rash, urticaria, dermatitis, angioneurotic edema, hyperhidrosis, fixed drug eruption, acute generalized exanthematous pustulosis, erythema multiforme, Stevens-Johnson syndrome.

Renal and Urinary Disorders: Not Known: Urinary retention.

General Disorders and Administration Site Conditions: Not Known: Malaise, pyrexia.

The following adverse reactions have been observed with cetirizine, the principal metabolite of Dormirax: Thrombocytopenia, aggression, depression, tic, dystonia, paresthesia, oculogyric crisis, diarrhea, dysuria, enuresis, asthenia, edema, increased weight and could potentially occur with Dormirax.