Doxepin (Silenor, Sinequan): How This TCA Works for Depression, Anxiety, and Sleep

Last updated: August 22, 2026

Doxepin is a tricyclic antidepressant. Historic capsule and liquid brands include Sinequan. Low-dose tablets sold as Silenor treat insomnia with trouble staying asleep. The same molecule is not the same product: 10 to 150 mg capsules and concentrate target depression and anxiety. 3 mg and 6 mg tablets target sleep maintenance. It is not a controlled substance. A licensed telehealth clinician can often start or continue oral doxepin after a full history, but glaucoma, urinary retention, recent MAOIs, and next-day impairment still need a careful screen.

This guide is educational. It is not a diagnosis and it is not a promise that any clinician will prescribe doxepin.

Looking for depression or sleep-related mood care online? Klarity Health has 2,000+ licensed providers. Many visits happen by video. Coverage varies by plan. Self-pay is also an option. See online depression treatment options or browse conditions.

TLDR

• MedlinePlus splits doxepin into two monographs: depression/anxiety (capsules and concentrate) and insomnia (Silenor tablets). Do not mix those instructions (MedlinePlus a682390; MedlinePlus a617017).
• Silenor is indicated for insomnia characterized by difficulty with sleep maintenance. Initial dose: 6 mg once daily for adults and 3 mg once daily for older adults, within 30 minutes of bedtime. Do not take within 3 hours of a meal. Plan 7 to 8 hours in bed (DailyMed Silenor setid 1bec1223).
• Capsule products are a TCA for depression and anxiety. Strengths commonly include 10, 25, 50, 75, 100, and 150 mg plus 10 mg/mL concentrate. Typical depression/anxiety starts often land in the 25 to 75 mg range and titrate; labels allow divided dosing. Max daily amounts in specialist use can reach 300 mg. Taper when stopping (StatPearls NBK542306; DailyMed capsules setid f3c242dd).
• Boxed warning on antidepressant products: suicidality in children, adolescents, and young adults to age 24. Children under 18 should not normally take doxepin for depression. Call 988 if you or someone you are with is in crisis (MedlinePlus).
• Do not combine with an MAOI, linezolid, or IV methylene blue. Wait 14 days after stopping an MAOI. Untreated narrow-angle glaucoma and urinary retention are usual reasons not to start. Cimetidine and other CYP2D6/CYP inhibitors can raise levels. Alcohol adds drowsiness.
• Not a controlled substance. Telehealth can manage many stable oral courses. Complex-sleep behaviors (sleep-driving, sleep-eating), sudden eye pain, inability to urinate, or overdose need emergency care, not a video follow-up.

Table of contents

• What doxepin is
• How it works
• Approved and related uses
• Doxepin dosage
• Side effects
• Warnings and who should not take it
• Interactions
• When telehealth is enough
• How a Klarity visit fits
• FAQ

What doxepin is

Doxepin hydrochloride is a tricyclic. Historic U.S. capsule and concentrate brands include Sinequan, now discontinued on many markets, with generics still common. Silenor is the 3 mg and 6 mg tablet brand labeled only for sleep-maintenance insomnia. Topical 5% cream exists for certain itchy dermatoses. Do not treat a cream, a 6 mg tablet, and a 75 mg capsule as interchangeable (MedlinePlus; StatPearls).

DEA schedule: none. That matters for telehealth. Unlike zolpidem or benzodiazepines, doxepin is not a scheduled hypnotic.

Related Klarity guides: amitriptyline, nortriptyline, trazodone, and the OTC sleep aid guide.

How it works

StatPearls describes doxepin as blocking reuptake of serotonin and norepinephrine, plus antagonism at histamine H1, alpha-1 adrenergic, and muscarinic receptors. At 3 to 6 mg, H1 blockade is the main sleep effect. At antidepressant doses, the TCA reuptake block and anticholinergic load both rise. The active metabolite is nordoxepin. CYP2D6 is the primary metabolic path, with CYP1A2, CYP2C9, and CYP3A4 also involved. Oral half-life is about 15 hours for doxepin and about 31 hours for nordoxepin. A high-fat meal raises AUC about 41%, which is why Silenor should stay away from a recent meal (StatPearls).

Approved and related uses

• Depression and anxiety: capsules and oral concentrate (MedlinePlus).
• Insomnia with sleep-maintenance trouble: Silenor 3 mg and 6 mg tablets (DailyMed Silenor).
• Sometimes used: chronic idiopathic urticaria (oral, specialist); topical cream for pruritus of atopic dermatitis or lichen simplex chronicus. Off-label neuropathic pain or migraine prevention appears in reviews. Those uses need a clinician rationale, not a blog post (StatPearls).

Doxepin does not replace CBT-I as first-line chronic insomnia care, and it does not replace a full bipolar or suicide-risk assessment when depression is the target.

Doxepin dosage

Follow the product on your bottle. Strengths and food rules differ.

Sources: DailyMed Silenor; MedlinePlus depression monograph; StatPearls.

If sleep has not improved in 7 to 10 days on Silenor, or it worsens, contact the prescriber. Do not double a missed bedtime dose.

Side effects

Common at antidepressant doses: dry mouth, constipation, dizziness, drowsiness, weight or appetite change, sweating, blurred vision, trouble urinating, sexual changes, sun sensitivity. Serious: yellowing of skin or eyes, fast or irregular heartbeat, unusual bruising, severe rash, angle-closure glaucoma symptoms (eye pain, colored rings, sudden vision change), suicidal thinking, seizures, overdose. Silenor trials more often list next-day drowsiness and nausea. Complex sleep behaviors need an immediate call to the prescriber and usually a stop (MedlinePlus; MedlinePlus insomnia).

Overdose can be fatal with TCAs. Irregular heartbeat, seizures, coma, fever, or collapse is a 911 event. Poison Control: 1-800-222-1222.

Warnings and who should not take it

• Boxed suicidality warning on antidepressant labeling through age 24. Family should know the watch list: new agitation, panic, insomnia, aggression, or talk of self-harm.
• Not approved as a first-line pediatric antidepressant. Safety is not established in children for Silenor.
• Glaucoma that is untreated and urinary retention: usual contraindications.
• MAOI, linezolid, IV methylene blue: do not combine. 14-day washout.
• Beers criteria: avoid typical TCA doses in many adults 65+. Silenor starts at 3 mg in older adults for that reason.
• Pregnancy and lactation: discuss with the obstetric and pediatric teams. StatPearls notes former pregnancy category C animal data and that nordoxepin appears in breast milk; nursing is generally not recommended without a specialist plan.

Interactions

Cimetidine can raise doxepin. Other sedating antihistamines (diphenhydramine, doxylamine) stack drowsiness with Silenor. Fluoxetine and other strong CYP2D6 inhibitors can require extra caution or a delay after fluoxetine. Alcohol and other CNS depressants add impairment. Do not drive the night you take Silenor until you know the next-day effect. Tell every clinician, including dentists, that you take doxepin.

When telehealth is enough

Oral doxepin is not scheduled, so a video visit can often start or refill it when the history is complete, blood pressure and eye/urine symptoms are screened, and the person can stay in bed 7 to 8 hours after a sleep dose. New starts for depression still need a suicide-risk and bipolar screen. Labs are not mandatory for every start the way they are for carbamazepine or clozapine, but liver disease, older age, and polypharmacy change the plan.

Stay in person or go to urgent care for: inability to urinate, sudden eye pain, jaundice, fainting, chest pain, suspected overdose, or complex sleep behaviors that put you or others at risk. Intramuscular products and dermatology cream plans sit outside a typical psychiatry video visit.

How a Klarity visit fits

Klarity Health connects people with 2,000+ licensed providers for online mental health and medical visits. A clinician may discuss doxepin, another antidepressant, CBT-I, or no medicine. Insurance may help pay for a visit. Coverage varies by plan. Verify benefits before you book. Self-pay is also an option.

See online depression treatment options · Browse conditions

Disclaimer: This article is for education only. It is not medical advice. Medication choice, dose, and monitoring belong to you and a licensed clinician. Insurance coverage for visits and prescriptions varies by plan. Confirm benefits before you schedule. If you are in crisis, call or text 988 or go to the nearest emergency department.

FAQ

Is doxepin the same as Silenor?

Silenor is low-dose doxepin (3 mg and 6 mg) labeled for sleep-maintenance insomnia. Higher-dose capsules and liquid are the older TCA products for depression and anxiety. Same molecule, different products and food rules.

Is doxepin a controlled substance?

No. It is not a DEA-scheduled drug.

How long until doxepin works?

Silenor often helps sleep in the first few nights. Antidepressant effect can take several weeks. Keep follow-up even if you feel better.

Can I take doxepin with melatonin or Unisom?

Do not stack sedating antihistamines without a clinician. Melatonin is a supplement with mixed evidence for chronic insomnia. See the OTC sleep aid guide.

What if I miss a Silenor dose?

Take it only if you can still stay in bed 7 to 8 hours. Do not double up the next night.