doxepin

Doxepin belongs to a class ofdrugscalledtricyclic antidepressants(TCAs) that are used primarily to treatdepressionandanxiety.

Other examples of TCAs includeamitriptyline(Elavil),nortriptyline(Pamelor),desipramine(Norpramin), and several others.Depressionis an all-pervasive sense of sadness and gloom. In some patients withdepression, an imbalance in levels of neurotransmitters in the brain may be the cause of thedepression.

Neurotransmitters are chemicals that nerves use to communicate with each other. Neurotransmitters affected by doxepin include serotonin, norepinephrine, acetylcholine, and histamine. Doxepin may elevate mood by raising the levels of serotonin and norepinephrine.

It also blocks the activity of acetylcholine and histamine. The FDA approved doxepin in March 1974.

What brand names are available for doxepin?

Silenor

Is doxepin available as a generic drug?

Yes

Do I need a prescription for doxepin?

Yes

The most common side effect of doxepin is drowsiness. Drowsiness improves as therapy continues. Other side effects associated with doxepin include:

• blurred vision,
• urinary retention(difficulty urinating),
• dry mouth,
• constipation,
• weight gainor loss,
• low blood pressurewhen rising from a sitting position (orthostatic hypotension),
• rash,
• hives,
• rapid or irregularheartrates,
• seizures, and
• hepatitis.

Doxepin also can cause elevated pressure in the eyes of some patients withglaucoma. Doxepin may dilate pupils which may trigger an angle closure attack in a patient with angle closureglaucoma.

Ifantidepressants, including doxepin, are discontinued abruptly, symptoms may include:

• dizziness,
• headache,
• nausea, and
• changes in mood.

Such symptoms of withdrawal may occur even when a few doses ofantidepressantare missed. Therefore, it is recommended that the dose of antidepressant be reduced gradually when therapy is discontinued.

Antidepressants increased the risk ofsuicidalthinking and behavior in short-term studies in children and adolescents with depression and other psychiatric disorders. Anyone considering the use of any antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening,suicidalthinking or behavior, and unusual changes in behavior.

The usual dose of doxepin for depression oranxietyis 25 to 300 mg daily administered at bedtime or in two or three divided doses. Doses greater than 300 mg daily are not more effective. Optimal improvement in depressive symptoms is seen after 2-3 weeks; anti-anxietyeffects occur much sooner.Insomniais treated with 3 to 6 mg daily taken 30 minutes before sleeping. Avoid taking doxepin with high fat meals because high fat meals increase the absorption of doxepin.

Tricyclic antidepressants , including doxepin, should not be taken with any of the monoamine oxidase inhibitor (MAOI) class of antidepressants (for example, isocarboxazid [Marplan], phenelzine [Nardil], tranylcypromine [Parnate],selegiline[Eldepryl], and procarbazine [Matulane]) or other drugs that inhibit monoamine oxidase such aslinezolid[Zyvox] and intravenousmethylene blue. Such combinations may lead toconfusion,high blood pressure,tremor,hyperactivity,coma, and death. Doxepin should not be administered for at least 14 days after stopping.

Drug that affect heart rhythm such asamiodarone(Cordarone),bepridil(Vascor), anddisopyramide(Norpace) should not be combined with doxepin since it also affects heart rhythm.

Cimetidine(Tagamet) increases the breakdown of doxepin by theliverand can increase doxepin blood levels, possibly causing side effects from doxepin.

There are no adequate studies of doxepin use inpregnantwomen.

It is not known if doxepin is secreted inbreast milk. There is one report of apnea (cessation ofbreathing) and drowsiness occurring in anursinginfant whose mother was taking doxepin.

What preparations of doxepin are available?

Capsules: 10, 25, 50, 75, 100, 150 mg; Liquid: 10 mg/ml

How should I keep doxepin stored?

Doxepin should be stored below 30 C (86 F) in a tight, light resistant container.