What You Need to Know About Imipramine Side Effects

Imipramine (brand name Tofranil) is a tricyclic antidepressant that's been used since the 1950s to treat depression, bedwetting in children, and several off-label conditions. Like all medications, it comes with side effects — some mild and temporary, others serious enough to require immediate medical attention.

This guide breaks down what to expect when you start Imipramine, which side effects are normal, and when you should call your doctor.

What Is Imipramine?

Imipramine is a tricyclic antidepressant (TCA) that works by blocking the reuptake of serotonin and norepinephrine in the brain. It's FDA-approved for depression and nocturnal enuresis (bedwetting) in children aged 6 and older. Doctors also prescribe it off-label for panic disorder, chronic pain, PTSD, and overactive bladder.

For a deeper look at how this medication works, see our guide on how Imipramine works.

Common Side Effects

Most people who take Imipramine will experience at least some of these side effects, especially during the first few weeks. Many improve as your body adjusts to the medication.

• Dry mouth — One of the most frequent complaints. Sipping water, chewing sugar-free gum, or using a saliva substitute can help.
• Drowsiness — Especially common when starting or increasing the dose. Taking Imipramine at bedtime can turn this into a benefit.
• Dizziness — Often related to orthostatic hypotension (a drop in blood pressure when standing up). Stand up slowly from sitting or lying positions.
• Constipation — The drug's anticholinergic effects slow down the gut. Increase fiber and water intake.
• Blurred vision — Usually mild and temporary. If it persists, let your doctor know.
• Weight gain — Some people gain weight over time on tricyclic antidepressants.
• Urinary retention — Difficulty starting or completing urination. More common in older men.
• Sweating — Excessive sweating, especially at night.
• Nausea — Usually improves after the first week or two.
• Fatigue — May feel unusually tired, especially early on.
• Orthostatic hypotension — Feeling lightheaded when standing up quickly.

Serious Side Effects

These side effects are less common but require prompt medical attention. Contact your doctor or go to the emergency room if you experience any of the following.

Suicidal Thoughts or Behavior

Imipramine carries an FDA black box warning about increased risk of suicidal thinking and behavior, particularly in children, adolescents, and young adults under 25. This risk is highest during the first few months of treatment or when doses are changed. If you or someone you know is having thoughts of self-harm, call 988 (Suicide and Crisis Lifeline) or go to the nearest emergency room.

Heart Rhythm Problems

Tricyclic antidepressants can cause cardiac arrhythmias and conduction abnormalities. Symptoms to watch for include rapid or irregular heartbeat, fainting, and chest pain. Your doctor may order an ECG before starting treatment, especially if you have a history of heart disease.

Seizures

Imipramine can lower the seizure threshold. People with epilepsy or a history of seizures are at higher risk. If you have a seizure while taking Imipramine, seek emergency care immediately.

Serotonin Syndrome

This rare but potentially life-threatening condition can occur when Imipramine is combined with other serotonergic drugs. Symptoms include agitation, confusion, rapid heart rate, high blood pressure, dilated pupils, muscle twitching, and high fever. See our drug interactions guide for more details.

Severe Allergic Reactions

Seek immediate help for rash, hives, swelling of the face or throat, or difficulty breathing.

Liver Problems

Rarely, Imipramine can cause hepatotoxicity. Signs include yellowing of the skin or eyes (jaundice), dark urine, and severe abdominal pain.

Manic Episodes

In patients with undiagnosed bipolar disorder, Imipramine can trigger a manic episode. Symptoms include racing thoughts, decreased need for sleep, impulsive behavior, and elevated mood.

Side Effects in Specific Populations

Elderly Patients

Older adults are more sensitive to Imipramine's side effects, especially orthostatic hypotension (which increases fall risk), urinary retention, and confusion. Doctors typically start elderly patients on lower doses — around 30 to 40 mg per day — and increase slowly.

Children

Imipramine is FDA-approved for bedwetting in children aged 6 and older, but it is not approved for depression in children. The suicidality risk is particularly important to monitor in younger patients.

Pregnant and Nursing Women

Imipramine is Pregnancy Category D, meaning there is evidence of risk to the fetus. It should only be used during pregnancy if the benefits clearly outweigh the risks. It is also excreted in breast milk and is not recommended while breastfeeding.

How to Manage Side Effects

Many common side effects can be reduced with simple strategies:

• Take it at bedtime — This helps with drowsiness and may improve sleep.
• Stay hydrated — Helps with dry mouth and constipation.
• Eat high-fiber foods — Counteracts constipation.
• Stand up slowly — Reduces dizziness from blood pressure drops.
• Avoid alcohol — Alcohol intensifies drowsiness and CNS depression.
• Use sugar-free gum or mints — Relieves dry mouth.
• Don't skip doses — Consistent dosing keeps blood levels stable and reduces symptom fluctuation.

If side effects are bothering you, don't stop Imipramine on your own. Stopping suddenly can cause withdrawal symptoms like nausea, headache, and irritability. Talk to your doctor about adjusting the dose or trying an alternative. For options, see our guide on alternatives to Imipramine.

Final Thoughts

Imipramine is a well-studied medication that has helped millions of people over the decades. Most side effects are mild and manageable, especially with the right strategies. But serious side effects like heart rhythm changes, seizures, and suicidal thoughts require immediate medical attention.

Talk openly with your doctor about what you're experiencing. They can adjust your dose, add supportive treatments, or switch you to another medication if needed. If you're looking for Imipramine at a good price, Medfinder can help you find it in stock near you.