A small number of children, teenagers, and young adults (up to 24 years of age) who took antidepressants ('mood elevators') such as phenelzine during clinical studies became suicidal (thinking about harming or killing oneself or planning or trying to do so). Children, teenagers, and young adults who take antidepressants to treat depression or other mental illnesses may be more likely to become suicidal than children, teenagers, and young adults who do not take antidepressants to treat these conditions. However, experts are not sure about how great this risk is and how much it should be considered in deciding whether a child or teenager should take an antidepressant. Children younger than 18 years of age should not normally take phenelzine, but in some cases, a doctor may decide that phenelzine is the best medication to treat a child's condition.
You should know that your mental health may change in unexpected ways when you take phenelzine or other antidepressants even if you are an adult over age 24. You may become suicidal, especially at the beginning of your treatment and any time that your dose is increased or decreased. You, your family, or your caregiver should call your doctor right away if you experience any of the following symptoms: new or worsening depression; thinking about harming or killing yourself, or planning or trying to do so; extreme worry; agitation; panic attacks; difficulty falling asleep or staying asleep; aggressive behavior; irritability; acting without thinking; severe restlessness; and frenzied abnormal excitement. Be sure that your family or caregiver knows which symptoms may be serious so they can call the doctor when you are unable to seek treatment on your own.
Your healthcare provider will want to see you often while you are taking phenelzine, especially at the beginning of your treatment. Be sure to keep all appointments for office visits with your doctor.
The doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with phenelzine. Read the information carefully and ask your doctor or pharmacist if you have any questions. You also can obtain the Medication Guide from the FDA website: Web Site.
No matter what your age, before you take an antidepressant, you, your parent, or your caregiver should talk to your doctor about the risks and benefits of treating your condition with an antidepressant or with other treatments. You should also talk about the risks and benefits of not treating your condition. You should know that having depression or another mental illness greatly increases the risk that you will become suicidal. This risk is higher if you or anyone in your family has or has ever had bipolar disorder (mood that changes from depressed to abnormally excited) or mania (frenzied, abnormally excited mood) or has thought about or attempted suicide. Talk to your doctor about your condition, symptoms, and personal and family medical history. You and your doctor will decide what type of treatment is right for you.
Phenelzine is used to treat depression in people who have not been helped by other medications. Phenelzine is in a class of medications called monoamine oxidase inhibitors (MAOIs). It works by increasing the amounts of certain natural substances that are needed to maintain mental balance.
Phenelzine comes as a tablet to take by mouth. It is usually taken three times a day,. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take phenelzine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Your doctor will probably start you on a low dose of phenelzine and gradually increase your dose. After your symptoms have improved, your doctor will probably gradually decrease your dose. Follow these directions carefully.
Phenelzine controls the symptoms of depression but does not cure the condition. It may take 4 weeks or longer for you to feel the full benefit of phenelzine. Continue to take phenelzine even if you feel well. Do not stop taking phenelzine without talking to your doctor. Your doctor probably will want to decrease your dose gradually. If you suddenly stop taking phenelzine, you may experience withdrawal symptoms such as nightmares, agitation, loss of contact with reality, nausea, vomiting, and weakness.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Before taking phenelzine,
- tell your doctor and pharmacist if you are allergic to phenelzine or any other medications.
- tell your doctor if you are taking, have recently taken, or plan to take any of the following prescription and non-prescription medications: certain other antidepressants including amitriptyline (Elavil), amoxapine, clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), imipramine (Tofranil), maprotiline, mirtazapine (Remeron), nortriptyline (Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil);amphetamines such as amphetamine (in Adderall), benzphetamine (Didrex), dextroamphetamine (Dexedrine, Dextrostat, in Adderall), and methamphetamine (Desoxyn);bupropion (Wellbutrin, Zyban); buspirone (BuSpar); caffeine (No-Doz, Quick-Pep, Vivarin); cyclobenzaprine (Flexeril); dexfenfluramine (Redux) (not available in the U.S.); dextromethorphan (Robitussin, others); duloxetine (Cymbalta); epinephrine (Epipen, Primatene Mist); guanethidine (Ismelin) (not available in the U.S.); levodopa (Larodopa, in Sinemet); medications for allergies, cough and cold symptoms, hay fever; anxiety, sinus problems, or weight loss (diet pills, appetite suppressants); medications for seizures such as carbamazepine (Tegretol); narcotic medications for pain; nasal decongestants, including nose drops and sprays; other MAOIs such as isocarboxazid (Marplan); pargyline (not available in the U.S.), procarbazine (Matulane), tranylcypromine (Parnate), and selegiline (Eldepryl, Emsam, Zelapar); meperidine (Demerol); methyldopa (Aldomet); 'pep pills'; sedatives; selective serotonin reuptake inhibitors such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft);sleeping pills; tranquilizers; venlafaxine (Effexor); and medications containing alcohol (Nyquil, elixirs, others). Your doctor may tell you not to take phenelzine if you are taking or have recently stopped taking one or more of these medications.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, and herbal products you are taking or plan to take. Be sure to mention any of the following: barbiturates such as pentobarbital (Nembutal), phenobarbital (Luminal), and secobarbital (Seconal); beta blockers such as atenolol (Tenormin), labetalol (Normodyne), metoprolol (Lopressor, Toprol XL), nadolol (Corgard), and propranolol (Inderal); doxepin cream (Zonelon), insulin and oral medications for diabetes; and medication for high blood pressure including diuretics ('water pills'), and reserpine (Serpalan). Your doctor may need to change the doses of your medications and monitor you carefully for side effects.
- you should know that phenelzine may remain in your body for several weeks after you stop taking the medication. During the first few weeks after your treatment ends, tell your doctor and pharmacist that you have recently stopped taking phenelzine before you start taking any new medications.
- tell your doctor if you are taking any nutritional supplements, especially phenylalanine (DLPA)(contained in aspartame sweetened products such as diet sodas and foods, over-the-counter medications, and some prescription medications), rauwolfia, tyrosine, or tryptophan.
- tell your doctor if you have or have ever had pheochromocytoma (a tumor on a small gland near the kidneys) or heart or liver disease. Your doctor may tell you not to take phenelzine.
- tell your doctor if you use street drugs. Also tell your doctor if you have or have ever had high blood pressure; diabetes; seizures; schizophrenia (a mental illness that causes disturbed thinking, loss of interest in life, and strong or unusual emotions); agitation; or hyperactivity or other movement disorders.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking phenelzine, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking phenelzine.
- you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
- do not drink alcohol while you are taking phenelzine. Alcohol can make the side effects of phenelzine worse.
- you should know that phenelzine may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking phenelzine. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
You may experience a serious reaction if you eat foods that are high in tyramine during your treatment with phenelzine. Tyramine is found in many foods, including meat, poultry, fish, or cheese that has been smoked, aged, improperly stored, or spoiled; certain fruits, vegetables, and beans; alcoholic beverages; and yeast products that have fermented. Your doctor or dietitian will tell you which foods you must avoid completely, and which foods you may eat in small amounts. You should also avoid foods and drinks that contain caffeine during your treatment with phenelzine. Follow these directions carefully. Ask your doctor or dietitian if you have any questions about what you may eat and drink during your treatment.
Take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Phenelzine may cause side effects. Tell your doctor if any of the following symptoms are severe or do not go away:
- dry mouth
- weight gain
- decreased sexual ability
- uncontrollable shaking of any part of the body
- muscle twitching or jerking
Some side effects can be serious. If you experience any of the following symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:
- slow, fast, or pounding heartbeat
- neck stiffness or soreness
- chest pain
- wide pupils (black circles in the middle of the eyes)
- eyes more sensitive to light than usual
- swelling of face, throat, arms, hands, feet, ankles, or lower legs
- difficulty breathing or swallowing
- yellowing of the skin or eyes
Phenelzine may cause other side effects. Call your doctor if you experience any unusual problems while you are taking this medication.
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
- hallucinations (seeing things or hearing voices that do not exist)
- tightening of the jaw
- stiffly arched back
- coma (loss of consciousness for a period of time)
- fast, irregular pulse
- chest pain
- slowed breathing
- cool, clammy skin
Keep all appointments with your doctor and the laboratory. Your doctor will check your blood pressure regularly during your treatment with phenelzine.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: September 1, 2010.