Dopinex

Dopinex Capsule

Dopinex hydrochloride is one of a class of agents known as dibenzoxepin tricyclic antidepressant compounds. Although doxepin HCl does have H1 and H2 histamine receptor blocking actions, the exact mechanism by which doxepin exerts its antipruritic effect is unknown. It can produce drowsiness in significant numbers of patients, and this sedation may reduce awareness, including awareness of pruritic symptoms.

Dopinex inhibits serotonin and norepinephrine re-uptake by the presynaptic neuronal membrane increasing its synaptic conc in the CNS.

Uses

Dopinex Tablet is used for Anxiety disorders, Depression, Insomnia and Dopinex cream is used for the short-term (upto 8 days) management of moderate pruritus in adult patients with atopic dermatitis or lichen simplex chronicus.

Dopinex is also used to associated treatment for these conditions: Anxiety, Bipolar Affective Disorders, Depression, Depression, Involutional, Insomnia, Lichen simplex chronicus, Neuropathic Pain, Neurotic depression, Pruritus, Psychotic depressive disorder

Dopinex

Trade Name Dopinex
Generic Doxepin
Doxepin Other Names Doxepin, Doxepina, Doxepinum
Type Capsule
Formula C19H21NO
Weight Average: 279.3761
Monoisotopic: 279.162314299
Protein binding

Equilibrium dialysis indicates a mean protein binding of 75.5% for doxepin and 76% for desmethyldoxepin.

Therapeutic Class Local Antipruritic
Manufacturer Osho Pharma Pvt Ltd
Available Country India
Last Updated: June 23, 2021 at 9:09 am

Structure

Dopinex
Doxepin Structure

Dosage

Dopinex dosage

Cream: Adult and child over 12 years: apply thinly 3–4 times daily; usual max. 3 g per application; usual total max. 12 g daily; coverage should be less than 10% of body surface area.

Oral: Adult: As hydrochloride: Initially, 75 mg daily adjusted according to response; up to 300 mg daily in severely depressed patients; 25-50 mg daily in mildly affected patients. Total daily dose 100 mg should be given in divided doses.

May be taken with or without food.

Side Effects

For Cream: Drowsiness, local burning, stinging, irritation, tingling, rash; systemic side-effects such as antimuscarinic effects, headache, fever, dizziness, gastro-intestinal disturbances has been reported.

For Oral: Sedation, fatigue, weakness, lethargy, Dry mouth, Constipation, Blurred vision, Headache, Agitation, Insomnia, Anxiety, Nausea, vomiting, Sweating, Confusion, extrapyramidal symptoms (EPS), dizziness, paresthesia, Orthostatic hypotension, ECG changes, tachycardia, Increased LFTs, Tinnitus, Sexual dysfunction, Rash, Seizure, Agranulocytosis, Thrombocytopenia, Eosinophilia.

Precaution

Cautions should be exercised if there is susceptibility to angle-closure glaucoma, urinary retention, severe liver impairment, mania and also in pregnancy and breast-feeding. Drowsiness may affect performance of skilled tasks (e.g. driving) so patient should be careful.

Interaction

Concomitant use of tricyclic antidepressants with drugs that can inhibit cytochrome P450 2D6 like MAO inhibitors, cimetidine, alcohol may require lower doses than usually prescribed for either the tricyclic antidepressant or the other drug. MAO inhibitors should be discontinued at least two weeks prior to the cautious initiation of therapy with Dopinex cream.

Methylphenidate may increase plasma doxepin levels. Potentially Fatal: Potentiates hypertensive action of sympathomimetics. Increased anticholinergic effects with MAOIs. Additive CNS effects with anticholinergics, CNS depressants and alcohol.

Food Interaction

  • Avoid alcohol. Co-administration may enhance CNS adverse effects such as drowsiness and sedation.
  • Avoid St. John's Wort. Co-administration may lead to decreased serum concentrations of doxepin.

Volume of Distribution

The mean apparent volume of distribution of doxepin is reported to be of 20 L/kg.

Half Life

The mean elimination half-life is reported to be of 15 hours.

Clearance

The mean total apparent plasma clearance of a single oral dose of 50 mg doxepin in healthy individuals is 0.93 l/hr/kg.

Pregnancy & Breastfeeding use

Pregnancy: Category B- There are no adequate and well-controlled studies in pregnant women. This drug should be used during pregnancy only if clearly needed.

Nursing Mothers: Dopinex is excreted in human milk after oral administration. It is possible that doxepin may also be excreted in human milk following topical application of Dopinex cream.

Contraindication

Patients with untreated narrow angle glaucoma or a tendency to urinary retention because doxepin has an anticholinergic effect. Individuals who have shown previous sensitivity to any of its components. Hypersensitivity; mania, glaucoma, neonates (topical); lactation.

Special Warning

Use in Children: The use of Dopinex cream in pediatric patients is not recommended. Safe conditions for use of cream in children have not been established.

Use in Elderly Patients: Dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy.

Acute Overdose

If overdosage with topical application of Dopinex cream occur, the signs and symptoms may include cardiac dysrhythmias, severe hypotension, convulsions, and CNS depression, including coma. Changes in the electrocardiogram, particularly in QRS axis or width, are clinically significant indicators of tricyclic antidepressant toxicity. Other signs of overdose may include confusion, disturbed concentration, transient visual hallucinations, dilated pupils, agitation, hyperactive reflexes, stupor, drowsiness, muscle rigidity, vomiting, hypothermia, hyperpyrexia.

Storage Condition

Store at 15-30°C.

Innovators Monograph

Dopinex contains Doxepin see full prescribing information from innovator // generic/doxepin/doxepin-oral-tablets-prescribing-information" Monograph