Phenelzine (By mouth)


Phenelzine (FEN-el-zeen)
Treats depression. This medicine is a monoamine oxidase (MAO) inhibitor.

Brand Name(s)

There may be other brand names for this medicine.


When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to phenelzine. Do not use this medicine if you have high blood pressure, liver disease, heart disease, or severe kidney disease. Do not use this medicine if you have severe or frequent headaches, or pheochromocytoma (a tumor of the adrenal gland). You should not use this medicine if you have ever had a stroke, transient ischemic attack (TIA), or any other kind of cerebrovascular disease. There are many medicines that you should not use while you are using phenelzine. This includes medicine you can buy without a prescription (over-the counter). Make sure your doctor knows about all other medicines you are using. If you were using another MAO inhibitor (such as isocarboxazid, selegiline, tranylcypromine, Eldepryl®, Emsam®, Marplan®, or Parnate®) for your depression, you must wait at least 14 days before you can start using phenelzine. If you were using fluoxetine (Prozac®) for your depression, you must wait at least 5 weeks before you can start using phenelzine. If you stop using phenelzine, you must wait at least 14 days before starting another medicine for your depression. Some medicines for depression include amitriptyline, amoxapine, buspirone, carbamazepine, clomipramine, cyclobenzaprine, desipramine, doxepin, fluoxetine, imipramine, maprotiline, mirtazapine, nortriptyline, perphenazine, protriptyline, trimipramine, Anafranil®, Asendin®, Aventyl®, Buspar®, Carbatrol®, Elavil®, Flexeril®, Ludiomil®, Norpramin®, Pamelor®, Prozac®, Remeron®, Sinequan®, Surmontil®, Tegretol®, Tofranil®, Trilafon®, or Vivactil®. You should not use this medicine if you are also using an amphetamine (Desoxyn®, Dexedrine®), cocaine, epinephrine (Adrenalin Chloride®, Sus-Phrine®), levodopa (Dopar®, Larodopa®), methyldopa (Aldomet®), methylphenidate (Methylin®, Ritalin®), phenylalanine, tryptophan, or tyrosine. Do not use this medicine if you are using bupropion (Wellbutrin®), dextromethorphan (Benylin®), or meperidine (Demerol®). You should not use this medicine if you are also using citalopram (Celexa®), fluvoxamine (Luvox®), guanethidine (Ismelin®), paroxetine (Paxil®), sertraline (Zoloft®), or venlafaxine (Effexor®).

How to Use This Medicine

  • Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
  • You may need to use this medicine for as long as 4 weeks before you start feeling better.
  • This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor or pharmacist if you have any questions. Ask your pharmacist for the Medication Guide if you do not have one. Your doctor might ask you to sign some forms to show that you understand this information.
If a dose is missed:
  • If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine after you have finished your treatment. You will also need to throw away old medicine after the expiration date has passed.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
  • Make sure your doctor knows about all other medicines you are using. MAO inhibitors can be very dangerous if used with certain other medicines. You may need to wait at least 14 days after using this medicine before you start using another medicine. You must wait 5 weeks if you are changing from fluoxetine (Prozac®) to phenelzine (Nardil®).
  • Tell your doctor if you are also using certain blood pressure medicines (such as atenolol, metoprolol, propranolol, or Toprol®) or a diuretic or "water pill" (such as hydrochlorothiazide or HCTZ).
  • Do not drink alcohol while you are using this medicine. This includes Chianti wine, sherry, beer, non-alcohol or low alcohol beer and wine, and liqueurs. Tell your doctor if you are using any medicines that make you sleepy. These include sleeping pills, cold and allergy medicine, narcotic pain relievers, and sedatives.
  • Certain foods and drinks can cause dangerously high blood pressure in people who are using an MAO inhibitor. This is more common with aged, smoked, or fermented foods that are high in protein. Some foods you should not eat are cheese (especially strong or aged kinds), sour cream, caviar, liver, canned figs, soy sauce, sauerkraut, fava beans, yeasts, and yogurt. Avoid smoked or pickled meat, poultry, or fish, such as sausage, pepperoni, salami, anchovies, or herring. Do not eat dried fruit (such as raisins), bananas, avocados, raspberries, or very ripe fruit.
  • Do not drink or eat too much caffeine while you are using this medicine. Caffeine can be found in coffee, cola, chocolate, tea, and other foods and drinks. Ask your doctor how much caffeine is safe.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breast-feeding, or if you have Parkinson's disease, angina (chest pain), kidney disease, diabetes, or epilepsy. Your doctor also needs to know if you have schizophrenia, overactive thyroid, or a history of drug or alcohol addiction.
  • Your blood pressure might get too high while you are using this medicine. This may cause headaches, blurred vision, and other symptoms. You might need to keep track of your blood pressure between doctor appointments. If you think your blood pressure is getting too high, call your doctor right away.
  • For some children, teenagers, and young adults, this medicine can increase thoughts of suicide. Tell your doctor or your child's doctor right away if you or your child start to feel more depressed and have thoughts about hurting yourselves. Report any unusual thoughts or behaviors that trouble you or your child, especially if they are new or are getting worse quickly. Make sure the doctor knows if you or your child have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. Also tell the doctor if you or your child have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared. Let the doctor know if you, your child, or anyone in your family has bipolar disorder (manic-depressive) or has tried to commit suicide.
  • Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery or medical tests.
  • This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert. You may also feel lightheaded when getting up suddenly from a lying or sitting position, so stand up slowly.
  • Do not stop using this medicine suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:
  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
  • Bright light bothering your eyes more than normal.
  • Changes in behavior, or thoughts of hurting yourself or others.
  • Changes in vision or eye pain.
  • Fast, slow, or pounding heartbeat.
  • Feeling nervous, restless, anxious, agitated, or excited for no reason.
  • Fever, chills, cough, sore throat, and body aches.
  • Headache, especially in the back of your head.
  • Light-headedness or dizziness when getting up suddenly.
  • Problems in urination.
  • Seeing or hearing things that are not there, or severe confusion.
  • Seizures, tremors, or muscle twitching.
  • Stiff or sore neck.
  • Swelling in your hands, ankles, or feet.
  • Unusual sweating, sometimes with fever or cold skin.
  • Vomiting and nausea.
  • Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
  • Diarrhea, constipation, or stomach pain.
  • Dry mouth.
  • Trouble sleeping.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Review Date: 2011-02-04 Reviewed By: Keywords: ,
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