What is the most important information I should know about phenelzine?
There are many other medicines that can cause serious or life-threatening medical problems if you take them together with phenelzine. Do not take phenelzine before telling your doctor about all other prescription and over-the-counter medications you use, including vitamins, minerals, and herbal products. Keep a list with you of all the medicines you use and show this list to any doctor, dentist, or other healthcare provider who treats you.
You may have thoughts about suicide when you first start taking an antidepressant, especially if you are younger than 24 years old. Your doctor will need to check you at regular visits for at least the first 12 weeks of treatment.
Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
While you are taking phenelzine, you must not drink alcohol or eat foods that are high in tyramine, listed in the "What should I avoid while taking phenelzine?" section of this leaflet. Eating tyramine while you are taking phenelzine can raise your blood pressure to dangerous levels, causing symptoms that include sudden and severe headache, rapid heartbeat, stiffness in your neck, nausea, vomiting, cold sweat, vision problems, and sensitivity to light. Stop taking phenelzine and call your doctor at once if you have any of these symptoms.
Phenelzine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
What is phenelzine?
Phenelzine is a monoamine oxidase inhibitor (MAOI) that works by increasing the levels of certain chemicals in the brain.
Phenelzine is used to treat symptoms of depression that may include feelings of sadness, fear, anxiety, or worry about physical health (hypochondria). This medication is usually given after other anti-depressants have been tried without successful treatment of symptoms. Phenelzine is not for treating severe depression or bipolar disorder (manic depression).
Phenelzine may also be used for other purposes not listed in this medication guide.
What should I discuss with my doctor before taking phenelzine?
Do not use this medication if you have used another MAOI such as isocarboxazid (Marplan), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take phenelzine before another MAOI has cleared from your body.
Do not take phenelzine if you are allergic to it, or if you have:
- pheochromocytoma (tumor of the adrenal gland);
- congestive heart failure;
- a history of liver problems; or
- if you need any type of surgery with anesthesia.
There are many other medicines that can cause serious or life-threatening medical problems if you take them together with phenelzine. The following drugs should not be used while you are taking phenelzine:
- diet pills, caffeine, stimulants, ADHD medication, asthma medication, over-the-counter cough and cold or allergy medicines;
- tryptophan (also called L-tryptophan);
- levodopa (Larodopa, Parcopa, Sinemet), methyldopa (Aldomet);
- meperidine (Demerol, Mepergan);
- furazolidone (Furoxone);
- procarbazine (Matulane);
- buspirone (BuSpar);
- bupropion (Wellbutrin, Zyban);
- dexfenfluramine (Redux);
- guanethidine (Ismelin);
- alcohol or medicines that make you sleepy (such as cold medicine, pain medication, muscle relaxers, and medicine for seizures, depression or anxiety); or
- antidepressants such as citalopram (Celexa), duloxetine (Cymbalta), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), paroxetine (Paxil), sertraline (Zoloft), or venlafaxine (Effexor).
If you have any of these other conditions, you may need a phenelzine dose adjustment or special tests:
- high blood pressure, heart disease;
- diabetes;
- schizophrenia;
- epilepsy or other seizure disorder; or
- if you have taken another antidepressant within the past 5 weeks.
You may have thoughts about suicide while taking an antidepressant, especially if you are younger than 24 years old. Tell your doctor if you have worsening depression or suicidal thoughts during the first several weeks of treatment, or whenever your dose is changed.
Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits for at least the first 12 weeks of treatment.
FDA pregnancy category C. It is not known whether phenelzine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication..
It is not known whether phenelzine passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
How should I take phenelzine?
Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.
Your doctor may occasionally change your dose to make sure you get the best results.
Your blood pressure will need to be checked often. Visit your doctor regularly.
It may take several weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve after 4 weeks of treatment.
Store at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. Overdose symptoms may include feeling drowsy or dizzy, severe headache, neck pain or stiffness, hallucinations, shallow breathing, fast and uneven heart rate, cold sweats, feeling like you might pass out, or seizure (convulsions).
What should I avoid while taking phenelzine?
While you are taking phenelzine you must not eat foods that are high in tyramine, including:
- aged or smoked meats, fermented meats, dry sausage (including salami, pepperoni, Lebanon bologna), liver, pickled herring;
- any spoiled or improperly stored meats, fish, or dairy products;
- beer and wine (including non-alcoholic beer or wine);
- cheese (other than cottage cheese or cream cheese);
- sauerkraut;
- over-the-counter supplements or cough and cold medicines that contain dextromethorphan or tyramine;
- large amounts of chocolate or caffeine;
- yogurt;
- fava beans;
- meat extracts; or
- yeast extracts (including Brewer's yeast).
You should become very familiar with the list of foods and medicines you must avoid while you are taking phenelzine. Eating tyramine while you are taking phenelzine can raise your blood pressure to dangerous levels which could cause life-threatening side effects.
Phenelzine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
What are the possible side effects of phenelzine?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
Stop using phenelzine and call your doctor at once if you have any of these serious side effects:
- sudden and severe headache, rapid heartbeat, stiffness in your neck, nausea, vomiting, cold sweat, sweating, vision problems, sensitivity to light;
- chest pain, fast or slow heart rate;
- swelling, rapid weight gain;
- agitation, unusual thoughts or behavior; or
- feeling light-headed, fainting.
Less serious side effects may include:
- dizziness;
- feeling weak or drowsy;
- sleep problems (insomnia);
- constipation, upset stomach;
- dry mouth, decreased urination; or
- impotence, difficulty having an orgasm.
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect phenelzine?
There are many other medicines that can cause serious or life-threatening medical problems if you take them together with phenelzine. Do not take phenelzine before telling your doctor about all other prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor. Keep a list with you of all the medicines you use and show this list to any doctor, dentist, or other healthcare provider who treats you.
Where can I get more information?
Your pharmacist can provide more information about phenelzine.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.
Copyright 1996-2020 Cerner Multum, Inc. Version: 2.02. Revision date: 12/15/2010.
