thoughtscape NP Psychiatry · Patient education
Trimipramine
Surmontil
A sedating tricyclic antidepressant. Mood benefit and next-day sleepiness need to be assessed separately.
Draft for review · Clinical content has not been revalidated for this website.
Do not combine with an MAOI • Store securely: an overdose can rapidly become life-threatening
What it is used for
Treats depression in adults. Its sedating effects may be useful when depression includes sleep difficulty, but sleepiness alone is not recovery.
Insomnia, anxiety, and pain uses are off-label, with varying evidence. It is not an approved treatment for schizophrenia or bipolar depression.
How it works
Its antidepressant action is not fully understood. It has several receptor effects and differs from many other tricyclic antidepressants.
Histamine and acetylcholine effects help explain drowsiness, dry mouth, and constipation. Receptor binding alone does not prove a separate clinical benefit.
What to expect over time
EARLY ON
Drowsiness, dry mouth, or dizziness may occur before mood improves. Take care when standing and do not drive while impaired.
DURING DOSE CHANGES
Review alertness, blood pressure, bowel and bladder symptoms. More medicine is not automatically better if adverse effects limit function.
OVER SEVERAL WEEKS
Mood benefit usually takes several weeks. Keep follow-ups and compare sleep, daily function, and depressive symptoms, not sedation alone.
Taking your medication
Take the exact capsule dose at the times prescribed. Some schedules use divided doses, others bedtime dosing; do not combine doses yourself.
Avoid alcohol and check new medicines or supplements first. Rise slowly from sitting or lying; do not drive until you know the effects.
Do not take extra doses or stop suddenly. Ask for a taper plan and what to do after several missed doses. Keep capsules out of children's reach.
When to get help
Fainting, chest pain, a pounding or irregular heartbeat, seizure, or breathing difficulty needs urgent assessment; severe symptoms warrant 911.
Painful red eyes with vision changes, inability to urinate, or severe abdominal pain/constipation needs urgent care. Fever with sore throat needs prompt review.
Report suicidal thoughts, major mood change, new confusion, or fever with stiff/twitching muscles urgently. Call 911 for immediate danger.
Early side effects
Drowsiness, dry mouth, constipation, blurred vision, sweating, nausea, and standing dizziness can occur. Report persistent symptoms or falls.
Other effects to discuss
Weight gain or sexual difficulties may occur. Report new memory problems, urinary difficulty, or troubling symptoms rather than assuming they are inevitable.
What to keep track of
Track mood, alertness, memory, weight, pulse, standing dizziness, bowel and bladder function. An ECG or blood tests may be needed depending on heart risk, symptoms, and other medicines. Report fainting, palpitations, fever with sore throat or yellow skin/eyes promptly. Older adults are more vulnerable to confusion and falls.
Before you start
Discuss bipolar symptoms, self-harm, or overdose risk, recent heart attack, rhythm problems, fainting, seizures, narrow-angle glaucoma, prostate, or urinary problems, constipation, thyroid disease, and liver or kidney disease. Review all medicines and prior antidepressants. Tell your dentist or surgical team before a procedure.
Medicines & interactions
MAOIs / urgent antibiotics
At least 14 days are needed between trimipramine and a psychiatric MAOI in either direction. Linezolid or IV methylene blue requires a supervised plan.
Other antidepressants / supplements
Serotonergic combinations can cause serious toxicity. Fluoxetine, paroxetine, and bupropion may raise exposure. Fluoxetine interactions can persist for weeks.
Alcohol / sedating or drying drugs
Alcohol, opioids, sleep aids, and some allergy/bladder medicines can add sedation, confusion, constipation, or urinary problems. Check every product.
Heart / blood-pressure medicines
Review rhythm drugs, guanethidine, decongestants, stimulants, and local anesthetics with epinephrine. Thyroid treatment can also affect cardiac risk.
Cimetidine / other metabolic drugs
Cimetidine (Tagamet) and quinidine can raise levels. Dose changes or blood-level checks may be needed; do not change treatment yourself.
Everyday tips
Keep track of mood and daily function as well as sleep. Report persistent grogginess or emotional changes; do not assume they mean the dose is right.
Rise slowly and reduce fall hazards. Ask about safer alternatives if confusion, urinary problems, or dizziness outweigh the benefit.
Use regular dental care and sugar-free gum for dry mouth. Appropriate fluids and fiber may help constipation; ask about a bowel plan if needed.
Use sun protection and avoid excess sun exposure. Bring an up-to-date medication list to visits and ask before adding cold remedies or supplements.
Your questions, answered
What if I miss a dose?
Take it when remembered unless the next dose is near; then skip. Never double. Ask about taking a missed nighttime dose during the day.
Can I stop when I feel better?
Plan a gradual taper. Sudden stopping may cause nausea, headache, feeling unwell, or sleep changes. Treatment duration depends on your relapse risk.
Will I need an ECG or blood tests?
Testing depends on symptoms, heart risk, and interactions. A drug level may help if toxicity or unusual response is suspected; it is not needed for everyone.
Pregnancy or breastfeeding?
Discuss plans before changing treatment. Human pregnancy data are limited; a better-studied breastfeeding option is preferred, especially for a newborn or preterm infant.
Storage & safety
Keep tightly closed at room temperature, away from moisture, children and pets; never share. Discuss smaller supplies if overdose is a concern. Suspected overdose needs immediate emergency assessment; call U.S. Poison Help 1-800-222-1222. Call 911 for collapse, seizure, breathing trouble, inability to wake, or imminent self-harm.
About this information
For general information only; not a substitute for individualized medical advice. This sheet does not cover every risk or interaction. Ask your prescriber or pharmacist before changing how you take this medication.
Sources
Educational inclusion does not mean this medication or its indications are treated at this practice. Review the guide for your exact product with your prescriber or pharmacist.