Jeffrey Panko NP Psychiatry · Patient education
Phenelzine
Nardil / Oral MAOI antidepressant
A guide for adults taking phenelzine.
Follow the directions on your prescription and your provider's recommendations.
Formulations: Oral tablets are usually taken in divided doses. Interaction precautions continue after the last dose because the enzyme effect takes time to wear off.
What it is used for
Phenelzine treats depression, often after other options have not helped sufficiently. It is also used off-label for selected anxiety conditions. Food and medication precautions are essential.
How it works
It irreversibly inhibits monoamine oxidase, reducing breakdown of serotonin, norepinephrine, and dopamine. It also reduces clearance of tyramine from certain foods.
What to expect over time
Sleep, energy, or appetite may change before mood improves. Benefit usually builds over several weeks; some conditions need a longer trial at a useful dose.
Track the symptoms you are treating and how you manage daily activities. Keep follow-up appointments. Schedule an earlier appointment if your mood gets worse.
Taking your medication
- Follow the prescribed schedule and written low-tyramine diet.
- If you miss a dose, take it when you remember unless it is almost time for the next dose. Then skip it. Do not double a dose.
- Have every prescription, OTC medicine, and supplement checked before use.
- Consult with your provider before stopping. Continue food precautions for two weeks afterward.
When to get help
Emergency symptoms. Get emergency care for a sudden severe headache, chest pain, a pounding heartbeat, neck stiffness, vomiting, or visual changes. These can signal a dangerous blood-pressure reaction. Fever with agitation and muscle rigidity may be serotonin syndrome.
Prompt medical advice. Contact your provider for marked dizziness, faintness, worsening depression, or unusually high energy with little need for sleep. Do not treat a suspected blood-pressure crisis with extra medication on your own.
If you feel unsafe or have thoughts of self-harm, call 911 or go to an emergency department.
Possible side effects
- Dizziness or low blood pressure when standing
- Sleep changes, fatigue, or headache
- Dry mouth or constipation
- Weight or sexual-function changes
Keeping track of treatment
Some side effects resolve with time; others may require a change of medication. Discuss persistent or bothersome side effects with your provider.
Antidepressants can increase suicidal thoughts in people under 25. Watch for changes in mood or behavior at any age, especially when starting treatment or changing a dose.
Have blood pressure checked. Review dizziness, sleep, and medication or food exposures. Keep the written interaction and diet instructions available.
If you take too much
For a suspected overdose, call Poison Control at 1-800-222-1222 immediately, even if you feel well. Call 911 for a seizure, collapse, trouble breathing, or inability to wake.
Before you start
Discuss heart or blood-vessel disease, uncontrolled high blood pressure, liver disease, seizures, bipolar symptoms, and planned surgery.
Discuss pregnancy, pregnancy plans, and breastfeeding with your provider. Treatment decisions should consider both the medication and the condition being treated.
Discuss liver disease, congestive heart failure, and pheochromocytoma; these can rule out use. Tell your provider about any planned anesthesia.
Medicines and interactions
Review all your medications with your provider, including over-the-counter medicines and supplements. Have new medications checked before taking them.
Many antidepressants, stimulants, decongestants, tramadol, meperidine, dextromethorphan, and other medicines must not be combined. A pharmacist should check every prescription, OTC medicine, and supplement.
Switching intervals depend on the other medicine. Many require at least 14 days; fluoxetine generally requires at least five weeks before an MAOI. Never manage a switch yourself.
Everyday tips
Choose fresh, properly refrigerated foods and avoid spoiled or aged protein foods. Ask about uncertain ingredients before eating them.
Tell dentists, emergency clinicians, and anesthesia teams that you take an MAOI. Carry a medication list or medical alert.
Your questions answered
Which foods need attention?
Avoid high-tyramine foods such as aged cheeses, fermented or cured meats, concentrated yeast extracts, certain fermented soy foods, and tap or unpasteurized beer. Follow your written diet guide during treatment and for two weeks afterward.
Can I take cold medicine?
Check first. Decongestants and some cough ingredients can cause dangerous reactions. The name on the front of a package is not enough; ingredients matter.
Storage and safety
Keep medication in its labeled container, away from excess heat and moisture and out of reach of children and pets. Do not share it. Ask a pharmacy about disposal of unused medication.
Sources
About this information
Educational handout; does not replace your prescription or provider's recommendations.
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.