Sinequan

Brand Name

Sinequan

Common Name

doxepin

In this drug factsheet:

• How does this medication work? What will it do for me?
• How should I use this medication?
• What form(s) does this medication come in?
• Who should NOT take this medication?
• What side effects are possible with this medication?
• Are there any other precautions or warnings for this medication?
• What other drugs could interact with this medication?

How does this medication work? What will it do for me?

Doxepin belongs to the family of medications known as tricyclic antidepressants. It is used to treat depression, especially when anxiety is one of the symptoms.

Doxepin is also used to treat people with alcoholism who also have anxiety or depression. Tricyclic antidepressants are believed to work by keeping the balance of natural chemicals (neurotransmitters) in the body, namely serotonin and norepinephrine.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

How should I use this medication?

The recommended adult daily dose of doxepin ranges from 75 mg to 300 mg in 3 divided doses. The usual starting dose is 25 mg 3 times daily. The total dose can be taken at bedtime once the final dose is reached (as long as the final dose is 150 mg per day or less). Lower doses may be needed for seniors.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

What form(s) does this medication come in?

10 mg
Each hard gelatin capsule with a pink opaque body and scarlet opaque cap, imprinted DX 10 and filled with white powder, contains 10 mg of doxepin. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, microcrystalline cellulose, stearic acid, and talc; gelatin capsule: gelatin, titanium dioxide, D&C Red No. 28, D&C Red No. 33, D&C Yellow No. 10, FD&C Blue No. 1, and FD&C Red No. 40; edible black ink: D&C Yellow No. 10, FD&C Blue No. 1, FD&C Blue No. 2, FD&C Red No. 40, iron oxide black propylene glycol, and shellac.   

25 mg
Each hard gelatin capsule with a pink opaque body and blue opaque cap, imprinted DX 25, and filled with white powder, contains 25 mg of doxepin. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, microcrystalline cellulose, stearic acid, and talc; gelatin capsule: gelatin, titanium dioxide, D&C Red No. 28, FD&C Blue No. 1, and FD&C Red No. 40; edible black ink: D&C Yellow No. 10, FD&C Blue No. 1, FD&C Blue No. 2, FD&C Red No. 40, iron oxide black propylene glycol, and shellac.  

50 mg
Each hard gelatin capsule with a light beige opaque body and pink opaque cap, imprinted DX 50, and filled with white powder, contains 50 mg of doxepin. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, microcrystalline cellulose, stearic acid, and talc; gelatin capsule: gelatin, titanium dioxide, D&C Red No. 28, D&C Yellow No. 10, FD&C Blue No. 1, and FD&C Red No. 40; edible black ink: D&C Yellow No. 10, FD&C Blue No. 1, FD&C Blue No. 2, FD&C Red No. 40, iron oxide black propylene glycol, and shellac.  

75 mg
Each hard gelatin capsule with a light beige opaque body and light beige opaque cap, imprinted DX 75, and filled with white loose granules or slug, contains 75 mg of doxepin. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, microcrystalline cellulose, stearic acid, and talc; gelatin capsule: gelatin, titanium dioxide, D&C Red No. 28, D&C Yellow No. 10, and FD&C Blue No. 1; edible black ink: D&C Yellow No. 10, FD&C Blue No. 1, FD&C Blue No. 2, FD&C Red No. 40, iron oxide black propylene glycol, and shellac.   

100 mg
Each hard gelatin capsule with a light beige opaque body and blue opaque cap, imprinted DX 100, and filled with white loose granules or slug, contains 100 mg of doxepin. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, microcrystalline cellulose, stearic acid, and talc; gelatin capsule: gelatin, titanium dioxide, D&C Red No. 28, D&C Yellow No. 10, and FD&C Blue No. 1; edible black ink: D&C Yellow No. 10, FD&C Blue No. 1, FD&C Blue No. 2, FD&C Red No. 40, iron oxide black propylene glycol, and shellac.  

Who should NOT take this medication?

Doxepin should not be taken by anyone who:

• is allergic to doxepin or to any of the ingredients of the medication
• is allergic to any other dibenzoxepin compounds
• is a child
• has acute congestive heart failure
• has blood disorders
• has glaucoma or increased eye pressure
• has just had a heart attack
• has severe liver disease
• has taken a MAO inhibitor (e.g., phenelzine, tranylcypromine) within the last 14 days
• has urinary retention

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• constipation
• dizziness
• drowsiness
• dry mouth
• flushing
• headache
• increased or decreased appetite
• low blood pressure
• nausea
• tiredness or weakness (mild)
• unpleasant taste
• vision problems (e.g., blurred vision)
• weight gain

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

agitation anxiety confusion decreased or increased sexual ability decreased or increased sweating difficulty speaking disorientation eye pain fast or irregular heartbeat hallucinations increased sensitivity to sunlight irritability

loss of balance control mask-like face nervousness or restlessness nightmares numbing or tingling of the fingers or toes problems urinating ringing or buzzing in the ears shuffling walk skin rash or itching tremors or shakiness trouble sleeping vomiting

Stop taking the medication and seek immediate medical attention if any of the following occur:

• seizures
• symptoms of a severe allergic reaction (e.g., swelling of face and tongue, difficulty breathing, hives)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Drowsiness/reduced alertness: Since doxepin may cause drowsiness, avoid driving or engaging in activities requiring mental alertness and physical coordination until you determine that the medication does not affect you in this way.

Heart diseases: Tricyclic antidepressant medications such as doxepin, particularly when taken in high doses, can cause abnormal heart rhythms. People with a history of heart disease and seniors should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Mania or hypomania: Doxepin may cause activation of mania or hypomania. People with a history of bipolar disorder should be closely monitored by their doctor while using this medication.

Medical conditions: People with reduced liver function or seizures should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Suicidal or agitated behaviour: People taking antidepressants such as doxepin may feel agitated (restless, anxious, aggressive, emotional, trouble sleeping, and feeling not like themselves), or they may want to hurt themselves or others. If you notice any changes in mood, behaviours, thoughts, or feelings in yourself or someone who is taking this medication, contact a doctor immediately. Your doctor will monitor you closely for behaviour changes, especially at the start of treatment or when your dose is increased or decreased.

Surgery: Using doxepin before, during, and after surgery may increase the risk of developing abnormal heart rhythms. The risks and benefits of continuing doxepin during elective surgery should be discussed with your doctor. Your doctor may recommend to stop or reduce the dose of doxepin several days prior to the scheduled surgery.

Thyroid disease: Patients who have an overactive thyroid (hyperthyroidism) or are taking thyroid medication should be monitored closely by their doctor while taking doxepin.

Withdrawal: Stopping this medication abruptly after taking it for a long time may produce nausea, headache, and malaise. Experiencing these symptoms does not mean you are addicted. Do not suddenly stop taking this medication if you have been taking it for a while. If you are to stop taking this medication, contact your doctor, who will advise you on how to gradually stop taking this medication.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if doxepin passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

What other drugs could interact with this medication?

There may be an interaction between doxepin and any of the following:

acetylsalicylic acid (ASA) alcohol alfuzosin altretamine anticholinergic medications (e.g., atropine) barbiturates (e.g., phenobarbital) benzodiazepines (e.g., diazepam, lorazepam) beta-2 agonists (e.g., salmeterol, formoterol, fenoterol, terbutaline) bupriopion carbamazepine chloroquine cholinesterase inhibitors (e.g., donepezil, galantamine, rivastigmine) cimetidine cinacalcet ciprofloxacin clonidine decongestant nasal sprays (e.g., oxymetazoline, phenylephrine, naphazoline) delavirdine desmopressin divalproex dronedarone duloxetine guanethidine lithium MAO inhibitors (e.g., phenelzine, moclobemide)

methyldopa methylphenidate metoclopramide nilotinib nonsteroidal anti-inflammatory drugs (NSAIDs; e.g., celecoxib, diclofenac, ibuprofen, naproxen) other medications that can cause sedation (e.g., sedatives, sleeping pills, anaesthetics) paroxetine pimozide propoxyphene protease inhibitors for HIV (e.g., ritonavir, lopinavir, tipranavir) quinidine quinine rifabutin rifampin SSRI antidepressants (e.g., fluoxetine, fluvoxamine) stimulant medications (e.g., appetite suppressants, amphetamines, epinephrine, norepinephrine) terbinafine tetrabenazine thioridazine tramadol valproic acid warfarin yohimbine

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

All material copyright MediResource Inc. 1996 – 2025. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/Sinequan