SINEQUAN (Doxepin)

What is this medication?

Doxepin, Silenor
Antidepressant; Tricyclic (Tertiary Amine)

Silenor/Doxepin is indicated for treatment of depression, and/or insomnia.

“ALERT: US Boxed Warning

Suicidality and antidepressant drugs:
Antidepressants increased the risk compared to placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies of major depressive disorder and other psychiatric disorders. Anyone considering the use of doxepin or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults >24 years of age; there was a reduction in risk with antidepressants compared to placebo in adults 65 years of age and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Doxepin is not approved for use in pediatric patients.”

How does this medication work?

Silenor/Doxepin increases the synaptic concentration of serotonin and norepinephrine in the central nervous system by inhibition of their reuptake by the presynaptic neuronal membrane and antagonizes the histamine (H1) receptor for sleep maintenance.

How should I take this medication?

Depression and/or Anxiety
Oral: Take 25mg to 50 mg as a single dose at bedtime or in divided doses; gradually increase based on response and tolerability to a maintenance dose of 100mg to 300mg daily.

Insomnia
Oral: Take 3mg to 6 mg once daily within 30 minutes of bedtime; maximum dose: 6 mg/day.

How to Take: Take within 30 minutes of bedtime on an empty stomach.  

You Need to Avoid:  Avoid large amounts of grapefruit and its juice (CYP3A4 inhibitor) and alcohol which may enhance the hypotensive effect.  

What should I watch for while using this medication?

Use with caution in cases of hypersensitivity to doxepin, dibenzoxepins, or any component of the formulation; glaucoma; urinary retention; use of MAO inhibitors within 14 days

Use with caution in patients with decreased gastrointestinal motility, paralytic ileus, urinary retention, BPH, xerostomia, or visual problems. 

Use with caution in patients who perform tasks that require mental alertness.

Use with caution in patients who are at risk of hypotensive episodes.

Use with caution in patients with hepatic impairment and renal impairment

There is an increased risk of hazardous sleep-related activities such as sleep-driving; cooking and eating food, making phone calls, and having sex while asleep have also been noted; amnesia may also occur. Discontinue treatment in patients who report any sleep-related episodes.

What if I miss a dose?

If you miss a dose of medication, try to take it as soon as possible.  However, if it is almost time for your next dose, take only that scheduled dose.  Do not take double or extra doses.

How should I store this medication?

Keep out of the reach of children at all times.  Store at room temperature, 59 to 86° F (15 to 30° C).  Protect from light.  Keep the container tightly closed.  Properly dispose of any unused medication after the expiration date.

What are the possible side effects of using this medication?

Well tolerated, most side effects are transient and mild to moderate in nature.  The most common side effects include:

1-10%

Cardiovascular: Hypertension (chronic insomnia patients ≤3%), edema, flushing, hypotension, tachycardia

Central Nervous System: Sedation (chronic insomnia patients 6% to 9%), dizziness (chronic insomnia patients ≥1%), ataxia, chills, confusion, disorientation, drowsiness, extrapyramidal reaction, fatigue, hallucination, headache, numbness, paresthesia, seizure, tardive dyskinesia

Dermatologic: Alopecia, diaphoresis (excessive), pruritus, skin photosensitivity, skin rash

Endocrine & Metabolic: Altered serum glucose, change in libido, galactorrhea, gynecomastia, SIADH, weight gain

Gastrointestinal: Nausea (chronic insomnia patients 2%), gastroenteritis (chronic insomnia patients ≤2%), anorexia, aphthous stomatitis, constipation, diarrhea, dysgeusia, dyspepsia, vomiting, xerostomia

Genitourinary: Breast hypertrophy, testicular swelling, urinary retention

Hematologic & Oncologic: Agranulocytosis, eosinophilia, leukopenia, purpura, thrombocytopenia

Hepatic: Jaundice

Neuromuscular & Skeletal: Tremor, weakness

Ophthalmic: Blurred vision

Otic: Tinnitus

Respiratory: Upper respiratory tract infection (chronic insomnia patients 4%), exacerbation of asthma