Sinequan (Doxepin Hydrochloride)

Do’s

• Take Sinequan by mouth, as directed by your healthcare provider, typically 1 to 3 times daily.
• If taking it once a day, take it at bedtime to minimize daytime sleepiness.
• Follow your healthcare provider's instructions carefully regarding dosage and duration of use.
• Take it consistently at the same time(s) each day for best results.
• Continue taking Sinequan even if you feel well. Don't stop it without consulting your healthcare provider to avoid withdrawal symptoms.
• Report any new or worsening symptoms to your healthcare provider promptly, especially concerning suicidal thoughts.

Don'ts

• Don't increase your dose or take Sinequan more often or for longer than prescribed.
• Don't expect immediate relief. It may take up to 3 weeks to feel the full effect, although some improvement might be seen within a week.
• Don't abruptly stop taking Sinequan. Your healthcare provider will develop a tapering plan to gradually reduce your dosage and minimize withdrawal symptoms.

Common side effects:

• Drowsiness
• Blurred vision
• Dry mouth
• Constipation
• Weight changes
• Low blood pressure when standing (orthostatic hypotension)
• Rash
• Hives
• Rapid or irregular heart rates
• Seizures
• Hepatitis

Serious side effects that may require immediate medical attention include:

• Heartburn that doesn't go away
• Mental/mood changes (such as anxiety, agitation, confusion)
• Shaking
• Severe stomach/abdominal pain
• Severe dizziness
• Fast/irregular heartbeat
• Fainting
• Seizures
• Eye pain/swelling/redness
• Widened pupils
• Vision changes (such as seeing rainbows around lights at night)
• Serious allergic reactions, including rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing

This is not an exhaustive list, and other side effects may occur. If you experience any unusual or severe side effects while taking Sinequan,  contact your healthcare provider for medical advice.

Be sure to tell your healthcare provider about any allergies you have before taking Sinequan, including allergies to doxepin, other tricyclic antidepressants, or any inactive ingredients.

Inform your healthcare provider about your medical history, especially of:

• Bleeding problems
• Breathing problems
• Liver problems
• Recent heart attack
• Problems urinating (such as due to an enlarged prostate)
• Overactive thyroid (hyperthyroidism)
• Personal or family history of glaucoma (angle-closure type)
• Personal or family history of mental/mood conditions (such as bipolar disorder, psychosis)
• Family history of suicide
• Seizures
• Conditions that may increase your risk of seizures (such as other brain disease, alcohol/sedative withdrawal)

Sinequan may cause irregular heartbeat (QT prolongation). This can be serious and requires immediate medical attention.

The risk of QT prolongation is increased by certain medical conditions and medications. Tell your healthcare provider about all medications you take and if you have any of these 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)

Sinequan may cause dizziness, drowsiness, or blurred vision. Avoid driving, operating machinery, or activities requiring alertness until you know how the medication affects you. Limit alcoholic beverages and talk to your healthcare provider if you are using marijuana.

Inform your healthcare provider about all medications you take before having surgery.

Sinequan may make you more sensitive to the sun. Limit sun exposure and use sunscreen and protective clothing.

If you have diabetes, this drug may affect your blood sugar levels. Monitor your blood sugar regularly and tell your healthcare provider of the results.

Older adults may be more sensitive to side effects, especially dry mouth, dizziness, drowsiness, confusion, difficulty urinating, and QT prolongation.

Sinequan should only be used during pregnancy if clearly necessary. Discuss the risks and benefits with your healthcare provider. Babies born to mothers who take Sinequan late in pregnancy may experience withdrawal symptoms.

Sinequan passes into breast milk and may harm your baby. Breastfeeding is not recommended while taking Sinequan. Consult with your healthcare provider before breastfeeding.

Since untreated mental/mood problems can be serious, do not stop using Sinequan unless directed by your healthcare provider. Discuss the risks and benefits of using Sinequan during pregnancy if you are planning pregnancy, become pregnant, or think you may be pregnant.