SIDE EFFECTS: Burning/stinging at the application site, drowsiness, dizziness, dry mouth, blurred vision, or changes in taste may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. To relieve dry mouth, suck on (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if any of these unlikely but serious side effects occur: severe constipation, loss of coordination, ringing in the ears, persistent heartburn, mental/mood changes (e.g., agitation, confusion, depression), muscle weakness/spasms, numbness/tingling of the hands/feet, restlessness, decreased sexual ability/interest, trouble urinating, swelling of the hands/feet, weight gain. Tell your doctor right away if any of these rare but very serious side effects occur: easy bruising/bleeding, persistent nausea/vomiting, signs of infection (e.g., fever, persistent sore throat), pain/redness/swelling of arms or legs, severe stomach/abdominal pain, dark urine, yellowing eyes/skin. Seek immediate medical attention if any of these rare but very serious side effects occur: slurred speech, fast/irregular heartbeat, vision changes, fainting, weakness on one side of the body, seizures. A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before using doxepin, tell your doctor or pharmacist if you are allergic to it, or to other tricyclic antidepressants (e.g., amitriptyline); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: certain eye problem (narrow-angle glaucoma), problems urinating (e.g., due to enlarged prostate). Before using this medication, tell your doctor or pharmacist your medical history, especially of: breathing problems (e.g., bronchitis, emphysema), long-term constipation, long-term heartburn, diabetes, eating disorders (e.g., bulimia), certain eye problem (open-angle glaucoma), heart problems (e.g., irregular heartbeat), kidney problems, liver problems, overactive thyroid (hyperthyroidism), personal or family history of mental/mood conditions (e.g., bipolar disorder, psychosis, suicide), seizures, conditions that may increase your risk of seizures (e.g., other brain disease, alcohol withdrawal). Doxepin may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away. The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using doxepin, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death). Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using doxepin safely. This drug may make you dizzy or drowsy or blur your vision. Alcohol or marijuana can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana. To reduce dizziness and lower the risk of fainting, get up slowly when rising from a sitting or lying position. Before having surgery, tell your doctor or dentist that you are using this medication. If you have diabetes, this drug may affect your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination or signs of low blood sugar such as sudden sweating, shaking, fast heartbeat, hunger, blurred vision, dizziness, or tingling hands/feet. Your doctor may need to adjust your diabetes medication, exercise program, or diet. Older adults may be more sensitive to the side effects of this drug, especially dizziness, drowsiness, confusion, difficulty urinating, and QT prolongation (see above). During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. This medication passes into breast milk and could have undesirable effects on a nursing infant. Therefore, breast-feeding is not recommended while using this drug. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (such as prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug are: anticholinergics (e.g., atropine, belladonna alkaloids, scopolamine, drugs for Parkinson's disease such as benztropine), arbutamine, certain drugs for high blood pressure (e.g., clonidine, guanadrel, guanethidine), cisapride, digoxin, disopyramide, halofantrine, lithium, thyroid medication, valproic acid, drugs affecting liver enzymes that remove doxepin from your body (e.g., barbiturates such as phenobarbital, cimetidine, haloperidol, phenothiazines such as thioridazine, St. John's wort, terbinafine, certain drugs for heart rhythm such as flecainide/propafenone, certain HIV protease inhibitors such as fosamprenavir, certain anti-seizure drugs such as phenytoin, antidepressants such as amitriptyline, duloxetine, fluvoxamine, paroxetine, sertraline, trazodone). Taking MAO inhibitors with this medication may cause a serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine) during treatment with this medication. Most MAO inhibitors should also not be taken for two weeks before and after treatment with this medication. Ask your doctor when to start or stop taking this medication. Many drugs besides doxepin may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, pimozide, quinidine, procainamide, sotalol, macrolide antibiotics (such as erythromycin), sparfloxacin, among others. Therefore, before using doxepin, report all medications you are currently using to your doctor or pharmacist. Tell your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana, drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine). Check the labels on all your medicines (such as antacids, allergy or cough-and-cold products, diet aids) because they may contain cimetidine, ingredients that cause drowsiness, or decongestants/stimulants that could increase your heart rate or blood pressure. Ask your pharmacist about using those products safely.

OVERDOSE: This medicine may be harmful if swallowed. If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose or swallowing may include: confusion, hallucinations, big/wide pupils, fast/irregular heartbeat, severe dizziness, fainting, seizures, loss of consciousness.