Other Names: Adapin, Zonalon

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Sinequan (doxepin) belongs to a class of similar drugs called tricyclic antidepressants. Sinequan is prescribed to relieve depression, panic disorders, depression related to alcoholism or major illness, psychotic depression, chronic pain from a variety of conditions, fibromyalgia, reduce the incidence of chronic headache or migraine, ulcers, itching, and insomnia. Sinequan generally relieves tension, fear, guilt, and worry, while improving mood, energy, and sleep.

It may take a few weeks to experience the full benefits of Sinequan treatment; individuals taking it are encouraged to expect up to a 30 day wait before seeing improvement. Sinequan's effectiveness depends on building up a steady dose of the medication in your body and maintaining it over time. Do not skip doses, even if you feel you do not need them, as this may reduce the effectiveness of Sinequan. This medication will commonly be prescribed for no more than 6 months, at which time your doctor may want to evaluate your treatment or recommend tests to see if you're having any physical reactions to the medication you may not be aware of.

Sinequan is available only by prescription.

Sinequan Side Effects

Side effects are most likely during Sinequan treatment, particularly sleepiness, in the first few days of taking this medication. If any side effect doesn't clear up within a week, or if you have a very strong reaction, consult your doctor immediately. Many of the rare and serious side effects are more common in the elderly or with higher doses.

Sinequan may cause drowsiness and affect your motor functions. Be familiar with how you react to this medication before driving or performing any hazardous task.

Common Sinequan Side Effects: constipation or difficulty urinating (more likely in elderly patients), dizziness (try standing slowly), drowsiness (problems with fatigue may be reduced by taking Sinequan in the evening or at bedtime), dry mouth (consult dentist if it lasts longer than two weeks), sensitivity to sunlight (Wear sunglasses, protective clothing, and sunblock. Do not use sunlamps or tanning beds.), temperature sensitivity (avoid saunas, jacuzzis, and exposure to extreme cold), or weight gain.

Occasional Sinequan Side Effects: blood sugar changes, dental cavities, fainting, headache, hives, increased appetite, indigestion, nausea, rash, shaking, swollen face or tongue, unsteadiness, weakness. If you become dizzy or faint when rising from sitting or lying down, getting up slowly may help. If this condition worsens you should contact your doctor. Indigestion and nausea may be relieved by taking Sinequan with food; unless your doctor has instructed you otherwise, Sinequan is best taken with food in most cases.

Rare Sinequan Side Effects: breast enlargement, breast milk secretion, brown or red spots on skin, change in sense of taste or hearing, irritated tongue or mouth, nightmare, sexual side effects (impotence, difficulty with orgasm), sweating, restless feeling, vomiting.

Contact your doctor immediately if any of the following rare side effects occur: confusion, hallucination, heart palpitation, hepatitis (allergic reaction), intestinal blockage, irregular heartbeat, liver toxicity (yellow skin and eyes, feeling of illness throughout the body), mania (sometimes seen in cases of manic-depression), numbness or tingling in extremities, paranoia (possible in schizophrenia), seizure, serious eye movement problems, very low blood pressure, water retention, or weakness in arms or legs. Watch for fatigue and weakness accompanied by abnormal bleeding or bruises, fever, or sore throat as this may indicate bone marrow depression. There is a small chance of developing serotonin syndrome, which may cause confusion, restlessness, lowered coordination, shivering or trembling, diarrhea, fever, sweating, twitching, or behaving with an excitement you can't control.

Side effects of dosage reduction can be minimized by stepping gradually off your treatment according to your doctor's advice. Rapidly stopping Sinequan could result in all-over discomfort, headache, or nausea. While slowly stopping Sinequan, you may experience agitation, irritability, sleep disturbances, or restlessness.

Cautions: Certain medical conditions, like a recent heart attack or pregnancy, are contraindications for Sinequan treatment. But your doctor should be advised of any of the following conditions, or any history of them, as you may require more careful monitoring or a dosage adjustment if your doctor decides that Sinequan is right for you.

• Allergy: Inform your doctor of any allergy to foods, colorings, or preservatives. If you have ever had an allergic reaction to another tricyclic antidepressant, or to Tegretol (carbamazepine), Ludiomil (maprotiline), or Desyrel (trazodone), Sinequan treatment may not be right for you.
• Bipolar disorder: Sinequan may worsen this condition.
• Blood cell disorder: Sinequan has resulted in rare cases in bone marrow depression, which may cause anemia or a reduced ability to fight off infection. Inform your doctor of any history regarding these conditions, and be alert for signs of unusual bleeding, bruising, weakness, fever, sore throat, or fatigue that doesn't go away in the first few days of treatment or with rest.
• Breathing problems: If you have asthma, hay fever, allergies, or chronic sinus conditions, be aware that some of the medications used for these conditions may increase the risk of serious heart complications when combined with Sinequan treatment. If you have asthma, Sinequan may make this condition worse.
• Diabetes or Hypoglycemia: Sinequan may cause fluctuations in blood sugar levels. Also, there are rare reports of Sinequan increasing numbness, tingling, or pain in the extremities. Consult your doctor about minimizing these effects.
• Difficulty urinating: Consult with your doctor, this medication may not be right for you.
• Enlarged prostate: Sinequan may worsen this condition.
• Heart problems: Do not take Sinequan if you have had a recent heart attack. Many heart medications may interact negatively with Sinequan, and certain medicine combinations may increase the likelihood of dangerous heart-related side effects. Inform your doctor of any history of spontaneous rapid heartbeat, irregular heartbeat, or heart-related chest pain.
• Intestinal blockage: Inform your doctor of any history of this disorder. Sinequan has, in rare cases, caused this condition.
• Irritable bowel or bladder: Constipation or difficulty urinating may result from Sinequan treatment, consult your doctor about minimizing these possible side effects.
• Kidney problems or failure: Your doctor will want to put you on a lower dose, as a reduction in kidney function decreases your ability to remove Sinequan from the body as needed. Periodic blood checks may be recommended.
• Liver problems: Your doctor will want to put you on a lower dose, as a reduction in liver function decreases your ability to remove Sinequan from the body as needed. Periodic blood checks may be recommended.
• Glaucoma: Consult with your doctor, especially with narrow-angle glaucoma. This condition may be a contraindication for Sinequan treatment.
• Mental illness: Sinequan may react badly or cause excessive central nervous system depression in combination with medications used to treat these conditions.
• Schizophrenia: Sinequan may increase paranoia.
• Seizure disorders: If you have a history of seizure disorders, or are presently being treated for one, your doctor may want to monitor you more carefully. Sinequan may interact with certain seizure treatments, and there is some (rare) risk of seizure as a side effect.
• Sexual problems: Sinequan may alter the libido, or inhibit orgasm in men and women. Inform your doctor of any history of prostate difficulties.
• Surgery: Sinequan may interact with certain medications used during surgery. Inform your anesthesiologist, dentist, or surgeon in advance that you take Sinequan, especially if you are not dealing with your regular doctor. Be aware that certain antibiotics should not be combined with Sinequan, as you may need antibiotic treatment after your procedure to reduce the risk of infection.
• Thyroid disorder: Sinequan may interact with your treatment for overactive or underactive thyroid conditions. Speak with your doctor about any history of these conditions.

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Sinequan (doxepin) may not mix well with all medications, either prescription or over the counter. Some medications should not be mixed at all, and with others your doctor may want to adjust your dose to decrease the risk of side effects. Consult with your doctor if you are already taking, or intend to take, any of the following.

• Airway spasm relaxants like Proventil (albuterol) or Sudafed may increase the risk of heart problems with doxepin.
• Alcohol - Even small amount of alcohol may lead to blackouts while being treated with doxepin; intoxication and central nervous system depression and toxicity may be highly amplified. Avoid cold medications containing ethanol (alcohol).
• Aldomet (methyldopa) may increase the risk of side effects.
• Amphetamines may increase the risk of heart problems.
• Antabuse (disulfiram) - Amitriptyline may amplify the effects of this medication.
• Antibiotics of the quinolone family like Avelox (moxifloxacin), Raxar (grepafloxacin), Tequin (gatifloxacin), or Zagam (sparfloxacin) can result in serious heart related complications. Never combine these with doxepin treatment.
• Anticoagulants like Coumadin (warfarin) may lead to excessive bleeding when combined with doxepin.
• Antihistamines like Benadryl (diphenhydramine) and Tavist may increase the risk of serious side effects.
• Antipsychotics - medications used to treat mental illness increase the risk of serious side effects from doxepin.
• Antiseizure medication like Cerebyx (fosphenytoin), Dilantin (phenytoin), or Tegretol (carbamazepine) may decrease levels of doxepin.
• Antispasmodics such as Bentyl or Donnatal.
• Antithyroid agents used to treat overactive thyroid conditions may increase the risk of serious side effects.
• Appetite suppressants like Phentermine/Adipex (fastin), Meridia (sibutramine), or Xenical (orlistat) may increase the risk of heart complications when mixed with doxepin.
• Benzodiazepines (a class of antidepressants, anti-panic agents, sleep medications, and muscle relaxants) such as Ativan (lorazepam), Dalmane (flurazepam), Valium (diazepam), Halcion (triazolam), Restoril (temazepam), Xanax (alprazolam), Tranxene-SD (clorazepate), Paxipam (halazepam), ProSom (estazolam), Klonopin (clonazepam), and others, may increase the risk of serious side effects, such as loss of motor skills. Amitriptyline may be combined with Librium(chlordiazepoxide) for anxiety or depression that resists treatment with one medication.
• Catapres (clonidine) - increases the risks of serious side effects with doxepin.
• Cylert (pemoline) may increase the risk of side effects.
• Demser (metyrosine) may increase the risk of side effects.
• Diflucan (fluconazole) may result in high levels of doxepin in the body.
• Ephedrine, pseudoephedrine - may increase the risk of heart complications, found in certain sinus and cold preparations. Avoid supplements containing the herb Ephedra.
• Epinephrine (adrenaline) may increase the risk of heart complications.
• Estrogen (oral contraceptives or estrogen replacement) may elevate blood levels of doxepin.
• Ginseng - Do not take this herb while using doxepin.
• Hylorel (guanadrel) - Amitriptyline may decrease the effectiveness of this medication.
• Indian snakeroot - Do not take this herb while using doxepin.
• Ismelin (guanethidine) - Amitriptyline may decrease the effectiveness of this medication.
• Isoprel (isoproterenol) may increase the risk of heart complications when used with doxepin.
• Lioresal (baclofen) - possible muscle weakness or memory problems.
• Kava kava - Do not take this herb while using doxepin.
• MAO inhibitors - Amitriptyline must never be mixed with MAO (monoamine oxidase) inhibitors, a class of antidepressants and antisenility drugs, such as Eldepryl (selegiline), Furoxone (furazolidone), Nardil (phenelzine), Marplan (isocarboxazid), or Parnate (tranylcypromine). Never use Sinequan within 2 weeks of starting or stopping an MAO inhibitor. Patients over 65 should allow a longer wait period between using doxepin and an MAO, as doxepin may stay in their system longer than in other patients. This drug combination could be fatal.
• Metrizamide - increases the risk of seizures.
• Narcotic pain medication like Codeine, Demerol (meperidine), Buprenex (buprenorphine), Darvon (propoxyphene), Dilaudid (hydromorphone), MS Contin or Kadian (morphine), nalbuphine, OxyContin (oxycodone), Percocet (oxycodone and acetaminophen), Stadol (butorphanol), Talwin compound (pentazocine), or Vicodin (hydrocodone and acetaminophen), Vicoprofen (hydrocodone and ibuprofen) may increase the central nervous system or respiratory (breathing) depressant effects of doxepin. Consult your doctor for advice on how to take these medications together safely.
• Neo-Synephrine (phenylephrine) may increase risk of serious heart complications.
• Nicotine - May speed the removal of doxepin from the body, possibly diminishing it's effectiveness.
• Norflex (orphenadrine) - Risk of oversedation.
• Orap (pimozide) may increase the risk of side effects.
• Parkinsonism medication like Cogentin or Larodopa
• Phenergan (promethazine) may increase the risk of side effects.
• Placidyl (ethchlorvynol)
• Protease inhibitors such as Agenerase (amprenavir), Norvir (ritonavir), and perhaps others, may lead to toxic levels of doxepin in the body.
• Provigil (modafinil) - May cause toxic buildups of tricyclic antidepressants.
• Quinidex (quinidine)
• Rauwolfia alkaloids such as Rauwiloid (alseroxylon), Harmonyl (deserpidine), Raudixin (rauwolfia serpentina), or Serpasil (reserpine) may increase the risk of side effects when mixed with doxepin.
• Reglan (metoclopramide) may increase the risk of side effects.
• Rhythmol (propafenone)
• Ritalin (methylphenidate)
• Sedatives like Fioricet (butalbital, acetaminophen, and caffeine), Fiorinal, Phenobarbitol, Seconal, or other barbiturates.
• Selective serotonin reuptake inhibitors (SSRIs) like Celexa (citalopram), Paxil (paroxetine), Prozac (fluoxetine), Luvox (fluvoxamine), or Zoloft (sertraline) should not be mixed with doxepin. They may increase the risk of serious side effects or lead to elevated levels of doxepin in the blood.
• Skeletal muscle relaxants such as Flexeril (cyclobenzaprine), Skelaxin (metaxalone), Soma (carisoprodol), or Robaxin (methocarbamol) may cause oversedation in combination with this medication.
• Sleep medication like Ambien (zolpidem), Sonata (zaleplon), or over the counter sleeping pills should be used with doxepin only as, and if, advised by your doctor.
• St. John's Wort - Do not take this herb while using doxepin.
• Tagamet (cimetidine) - increases risk of serious side effects.
• Tambocor (flecainide)
• Temaril (trimeprazine) may increase the risk of side effects.
• Tenex (guanfacine) - may decrease effectiveness of this medication.
• Thyroid hormones such as Synthroid.
• Tikosyn (dofetilide) - possible heart rhythm problems, do not mix with doxepin treatment.
• Tranquilizers such as Haldol (haloperidol), Mellaril (thioridazine), or Thorazine (chlorpromazine) may cause oversedation.
• Tricyclic antidepressants (any other) such as Asendin (amoxapine), Anafranil (clomipramine), Pertofrane or Norpramin (desipramine), Elavil (amitriptyline), Tofranil (imipramine), Aventyl or Pamelor (nortriptyline), Vivactil (protriptyline), and Surmontil (trimipramine), should never be mixed with Sinequan (doxepin). If you have ever had an allergic reaction to any of these medications, you should not take Sinequan.
• Ultram (tramadol) - increased risk of seizure, do not mix with doxepin treatment.
• Vascor (bepridil) - possible heart rhythm problems, do not mix with doxepin treatment.
• Vitamin C - Excessive amounts may interfere with doxepin treatment and increase the likelihood of appetite increase or weight gain.
• Wellbutrin/Zyban (bupropion)
• Yohimbe - Do not take this herb while using doxepin.

Sinequan is a central nervous system depressant, and should be used very cautiously in combination with any medication that warns it 'may cause drowsiness,' or increases your level of alertness. Over the counter medications and herbal supplements should be checked with your doctor or pharmacist if you are unsure about the safety of using them while taking Sinequan.

Sinequan Dosages

Sinequan dosage may be different for each individual. Be sure your doctor has clearly explained your dosage requirements and schedule to you. Your doctor may want to monitor your Sinequan treatment during the first few weeks to adjust your dosage gradually upwards if a lower dose doesn't give you the full expected benefit. A typical ongoing dose for mood disorders or depression in an average adult is 25 mg taken 3 times per day, and no more than 150 mg per day unless you are hospitalized. Children and seniors will likely start with, and continue to take, lower doses of Sinequan. If your doctor suggests taking a single dose, instead of divided doses, this should usually be taken at bedtime to reduce the chance of side effects during waking hours.

For ongoing treatment of insomnia, the effective dosage will usually be about 10-25mg per day, taken at bedtime. This drug should be effective for treating your insomnia within a couple days of use, if it will help at all. Some people with insomnia find that this medication either does not work, or significantly affects them the next day.

Sinequan Directions

If you miss a dose of Sinequan, take it as soon as you remember. If you take Sinequan once a day at bedtime, your doctor may advise you not to take the missed dose in the morning as certain side effects may be disturbing to you in the daytime. If you don't remember until it's time to take the next dose, skip the missed dose and resume your regular schedule. Do not take double doses of Sinequan, as this increases the risk of side effects.

Take Sinequan with food or milk, even if you take it just before bed, to decrease the risk of nausea. Take Sinequan on an empty stomach only if so advised by your doctor.

For the oral solution, take with water, milk, citrus juice, tomato juice, or prune juice. Do not mix with grape juice or any carbonated beverage, as this could decrease the effectiveness of the medication. Take immediately after mixing, do not store or allow to stand.

Inform your doctor, dentist, or anesthesiologist that you are taking Sinequan before any kind of surgery or medical test. This medication may interfere with certain test results. Sinequan should not be combined with certain medications given during surgery, or some antibiotics given after surgery.

Store Sinequan away from direct light and heat. Store in a dry location; avoid storing it in the bathroom, near sinks, or other areas where it may become damp. Do not freeze the liquid version of Sinequan. Do not use after the expiration date.

Keep Sinequan away from children; both when storing it, and when discarding any unused medication.

Sinequan may cause drowsiness or disorientation. Be cautious if you plan to drive or operate heavy machinery, avoid these activities if you find yourself feeling tired or experience slowed reactions.

Sinequan and Pregnancy

Sinequan has not been adequately studied in pregnant and nursing women. Advise your doctor if you are pregnant or plan to become pregnant. Your doctor may advise you not to breastfeed while you are taking Sinequan.

Sinequan and Children

Sinequan is not recommended in patients under 12 years of age. Use and dosage for older children would be determined individually by your doctor.

Sinequan and Seniors

Increased risk of side effects, particularly confusion, hallucination, or symptoms similar to Parkinson's disease. Individuals over 60 may also be more likely to experience drowsiness or unsteadiness. Symptoms will likely show in the first two weeks, careful monitoring is advised. Seniors may be more likely to take medications that react with Sinequan, they are advised to carefully check the warnings that accompany any other medications they take.

Seniors usually start at the lower dose of 25mg per day, taken at bedtime, to reduce the risk of side effects.

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The information contained in this document is provided for educational purposes and information only. It is not a substitute for consultation with a physician or Health professional, either to diagnose symptoms or prescribe treatment. Any dosages mentioned are general guidelines only, please follow the directions of your doctor or pharmacist exactly when taking medication. We have made every effort to ensure that this information is accurate, but only your doctor, physician or Health professional can say if a medication, a drug alternative or drug combination, is safe for you. Information intended for US residents only.