Before taking phenelzine, tell your doctor or pharmacist if you are allergic to it; 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.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: a certain kind of adrenal gland tumor (pheochromocytoma), cerebrovascular disease (e.g., stroke), heart problems (e.g., congestive heart failure, heart attack), high blood pressure, history of severe/frequent headaches, liver problems, severe kidney disease.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: personal/family history of mental/mood disorders (e.g., schizophrenia, bipolar disorder), family history of high blood pressure, heart disease (e.g., coronary artery disease, history of chest pain), mild/moderate kidney disease, diabetes, certain nervous system diseases (Parkinson’s syndrome, seizures), overactive thyroid (hyperthyroidism).
This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Avoid alcoholic beverages.
To minimize dizziness and the risk of fainting, get up slowly when rising from a sitting or lying position.
Before having surgery or any procedures requiring use of contrast dye (e.g., myelography), tell your doctor or dentist you are on this medication. You may need to stop taking this drug beforehand. Follow your doctor’s instructions carefully.
If you have heart disease, this medication may mask chest pain. Avoid strenuous exercise while taking this medication.
If you have diabetes, phenelzine may lower your blood sugar levels. Check your blood sugar regularly, and share the results with your doctor. Tell your doctor immediately if you have symptoms of low blood sugar such as cold sweat, shaking, rapid heart rate, fainting, and hunger. Your anti-diabetic medication or diet may need to be adjusted.
Caution is advised when using this drug in the elderly because they may be more sensitive to the effects of the drug, especially the effects on blood pressure.
This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.
Since untreated mental/mood problems (such as depression) can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss with your doctor the benefits and risks of using this medication during pregnancy.
It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.
Some products that may interact with this drug include: other antidepressants (including maprotiline, mirtazapine, nefazodone, TCAs such as amitriptyline/nortriptyline), appetite suppressants (such as diethylpropion), drugs for attention deficit disorder (such as atomoxetine, methylphenidate), certain antihistamines (azatadine, carbetapentane, chlorpheniramine), apraclonidine, bupropion, buspirone, carbamazepine, cyclobenzaprine, dextromethorphan, certain drugs for high blood pressure (such as guanethidine, methyldopa, beta blockers such as atenolol, clonidine, rauwolfia alkaloids such as reserpine, “water pills”/diuretics such as hydrochlorothiazide), other MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, procarbazine, rasagiline, selegiline, tranylcypromine), certain narcotic medications (such as fentanyl, meperidine, methadone, tapentadol), certain drugs for Parkinson’s (such as entacapone, levodopa, tolcapone), street drugs (such as LSD, mescaline), stimulants (such as amphetamines, cocaine, dopamine, epinephrine, phenylalanine), tetrabenazine, “triptan” migraine drugs (such as sumatriptan, rizatriptan), tramadol, tyrosine, tryptophan.
The risk of serotonin syndrome/toxicity increases if you are also taking other drugs that increase serotonin. Examples include street drugs such as MDMA/ “ecstasy,” St. John’s wort, certain antidepressants (including SSRIs such as fluoxetine/paroxetine, SNRIs such as duloxetine/venlafaxine), among others. The risk of serotonin syndrome/toxicity may be more likely when you start or increase the dose of these drugs.
Tell your doctor or pharmacist if you are using any of these medications before, during, or within 2 weeks after treatment with phenelzine. Tell your doctor or pharmacist if you have taken fluoxetine during at least 5 weeks before starting phenelzine. Discuss with your doctor how much time to wait between starting or stopping any of these drugs and taking phenelzine.
Also report the use of drugs which might increase seizure risk (decrease seizure threshold) when combined with phenelzine such as isoniazid (INH), phenothiazines (such as thioridazine), theophylline, or tricyclic antidepressants (such as imipramine) among others. Consult your doctor or pharmacist for details.
Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as: certain antihistamines (such as diphenhydramine), anti-seizure drugs (such as phenytoin), medicine for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, narcotic pain relievers (such as codeine), psychiatric medicines (such as chlorpromazine, lithium, risperidone, trazodone).
Check the labels on all your medicines (such as allergy, cough-and-cold products, decongestants, diet pills) because they may contain dextromethorphan, decongestants, stimulants, or drowsiness-causing ingredients. Ask your pharmacist about the safe use of those products.
It is very important that you follow special dietary restrictions in order to limit the amount of tyramine in your diet. Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas) or eating large amounts of chocolate. Caffeine can increase the side effects of this medication. Foods and beverages high in tyramine should be avoided while you are taking this medication and for at least 2 weeks after you stop using this medication.
Foods high in tyramine include: aged cheeses (cheddar, camembert, emmenthaler, brie, stilton blue, gruyere, gouda, brick, bleu, roquefort, boursault, parmesan, romano, provolone, liederdranz, colby, edam), aged/dried/fermented/salted/smoked/pickled/processed meats and fish (includes bacon, summer sausage, liverwurst, hot dogs, corned beef, pepperoni, salami, bologna, ham, mortadella, pickled or dried herring), banana peel, beef/chicken liver (stored, not fresh), bouillon cubes, commercial gravies, concentrated yeast extracts, fava beans, Italian green beans, broad beans, fermented bean curd, homemade yeast-leavened bread, kim chee (Korean fermented cabbage), orange pulp, overripe or spoiled fruits, packaged soups, red wine, sauerkraut, sherry, snow pea pods, sourdough bread, soy sauce, soybeans, soybean paste/miso, tofu, tap beer and ale, vermouth.
Moderate-to-low tyramine content foods include: alcohol-free beer, avocados, bananas, bottled beer and ale, chocolate and products made with chocolate, coffee, cola, cultured dairy products (such as buttermilk, yogurt, sour cream), distilled spirits, eggplant, canned figs, fish roe (caviar), green bean pods, pate, peanuts, port wine, raisins, raspberries, red plums, spinach, tomatoes, white wine.
Tell your doctor or pharmacist immediately if you notice symptoms of high blood pressure such as fast/slow heartbeat, vomiting, sweating, headache, chest pain, sudden vision changes, weakness on one side of the body, or slurred speech.
Contact your healthcare professionals (e.g., doctor, pharmacist, dietician) for more information, including recommendations for your diet.