Before using doxepin, tell your doctor or pharmacist if you are allergic to it, or to other tricyclic antidepressants (such as 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.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: problems urinating (such as due to enlarged prostate), breathing problems (such as bronchitis, emphysema), glaucoma, heart problems (such as irregular heartbeat), kidney problems, liver problems, overactive thyroid (hyperthyroidism), personal or family history of mental/mood conditions (such as bipolar disorder, psychosis, suicide), seizures, conditions that may increase your risk of seizures (such as 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 (cannabis) 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 (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
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. Breastfeeding is not recommended while using this medication. Consult your doctor before breastfeeding.