ANTIDEPRESSANTS,MONOAMINE OXIDASE (MAO) INHIBITOR (Systemic)

Some commonly used brand names are:

In the U.S.?

• Nardil ²
• Parnate ³
• Marplan ¹

In Canada?

• Nardil ²
• Parnate ³

Category

• Antidepressant?Isocarboxazid; Phenelzine; Tranylcypromine
• Antipanicagent?Phenelzine; Tranylcypromine
• Headache, tension, prophylactic?Phenelzine; Tranylcypromine
• Vascular headache prophylactic?Phenelzine; Tranylcypromine

Description

Monoamine oxidase (MAO) inhibitors are used to relieve certaintypes of mental depression. They work by blocking the action of a chemicalsubstance known as monoamine oxidase (MAO) in the nervous system.

Although these medicines are very effective for certain patients, theymay also cause some unwanted reactions if not taken in the right way. It isvery important to avoid certain foods, beverages, and medicines while youare being treated with an MAO inhibitor. Your health care professional willhelp you obtain a list to carry in your wallet or purse as a reminder of whichproducts you should avoid.

MAO inhibitors are available only with your doctor's prescription, in thefollowing dosage forms:

Oral
• Isocarboxazid
  • Tablets (U.S.)
• Phenelzine
  • Tablets (U.S. and Canada)
• Tranylcypromine
  • Tablets (U.S. and Canada)

Before Using This Medicine

In deciding to use a medicine,the risks of taking the medicine must be weighed against the good it willdo. This is a decision you and your doctor will make. For monoamine oxidase(MAO) inhibitors, the following should be considered:

Allergies?Tell your doctor if you have ever had any unusual orallergic reaction to any MAO inhibitor. Also tell your health care professionalif you are allergic to any other substances, such as foods, preservatives,or dyes.

Diet?Dangerous reactions such as sudden high bloodpressure may result when MAO inhibitors are taken with certain foods or drinks.The following foods should be avoided:

• Foods that have a high tyramine content (most common in foods thatare aged or fermented to increase their flavor), such as cheeses; fava orbroad bean pods; yeast or meat extracts; smoked or pickled meat, poultry,or fish; fermented sausage (bologna, pepperoni, salami, summer sausage) orother fermented meat; sauerkraut; or any overripe fruit. If a list of thesefoods and beverages is not given to you, ask your health care professionalto provide one.
• Alcoholic beverages or alcohol-free or reduced-alcohol beer and wine.
• Large amounts of caffeine-containing food or beverages such as coffee,tea, cola, or chocolate.

Pregnancy?A limited study in pregnant women showed an increasedrisk of birth defects when these medicines were taken during the first 3 monthsof pregnancy. In animal studies, MAO inhibitors caused a slowing of growthand increased excitability in the newborn when very large doses were givento the mother during pregnancy.

Breast-feeding?Tranylcypromine passes into the breast milk; itis not known whether isocarboxazid or phenelzine passes into breast milk.Problems in nursing babies have not been reported.

Children?Antidepressants must be used with caution in childrenwith depression. Studies have shown occurrences of children thinking aboutsuicide or attempting suicide in clinical trials for this medicine. More studyis needed to be sure antidepressants are safe and effective in children

Animal studies have shown that these medicines may slow growthin the young. Therefore, be sure to discuss with your doctor the use of thesemedicines in children.

Older adults?Dizziness or lightheadedness may be especially likelyto occur in elderly patients, who are usually more sensitive than youngeradults to these effects of MAO inhibitors.

Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. When you are takingMAO inhibitors, it is especially important that your health care professionalknow if you are taking any of the following:

• Amphetamines or
• Antihypertensives (high blood pressure medicine) or
• Appetite suppressants (diet pills) or
• Cyclobenzaprine (e.g., Flexeril) or
• Fluoxetine (e.g., Prozac) or
• Levodopa (e.g., Dopar, Larodopa) or
• Maprotiline (e.g., Ludiomil) or
• Medicine for asthma or other breathing problems or
• Medicines for colds, sinus problems, or hay fever or other allergies(including nose drops or sprays) or
• Meperidine (e.g., Demerol) or
• Methylphenidate (e.g., Ritalin) or
• Monoamine oxidase (MAO) inhibitors, other, including furazolidone(e.g., Furoxone), procarbazine (e.g., Matulane), or selegiline (e.g., Eldepryl),or
• Paroxetine (e.g., Paxil), or
• Sertraline (e.g., Zoloft), or
• Tricyclic antidepressants (amitriptyline [e.g., Elavil], amoxapine[e.g., Asendin], clomipramine [e.g., Anafranil], desipramine [e.g., Pertofrane],doxepin [e.g., Sinequan], imipramine [e.g., Tofranil], nortriptyline [e.g.,Aventyl], protriptyline [e.g., Vivactil], trimipramine [e.g., Surmontil])?Usingthese medicines while you are taking or within 2 weeks of taking MAO inhibitorsmay cause serious side effects such as sudden rise in body temperature, extremelyhigh blood pressure, severe convulsions, and death; however, sometimes certainof these medicines may be used with MAO inhibitors under close supervisionby your doctor

• Antidiabetics, oral (diabetes medicine you take by mouth) or
• Insulin?MAO inhibitors may change the amount of antidiabeticmedicine you need to take

• Bupropion (e.g., Wellbutrin)?Using bupropion while you aretaking or within 2 weeks of taking MAO inhibitors may cause serious side effectssuch as seizures

• Buspirone (e.g., BuSpar)?Use with MAO inhibitors may causehigh blood pressure

• Carbamazepine (e.g., Tegretol)?Use with MAO inhibitors mayincrease seizures

• Central nervous system (CNS) depressants (medicines that cause drowsiness)?Usingthese medicines with MAO inhibitors may increase the CNS and other depressanteffects

• Cocaine?Cocaine use by persons taking MAO inhibitors, includingfurazolidone and procarbazine, may cause a severe increase in blood pressure

• Dextromethorphan?Use with MAO inhibitors may cause excitement,high blood pressure, and fever

• Trazodone or
• Tryptophan used as a food supplement or a sleep aid?Use ofthese medicines by persons taking MAO inhibitors, including furazolidone andprocarbazine, may cause mental confusion, excitement, shivering, trouble inbreathing, or fever

Other medical problems?The presence of other medicalproblems may affect the use of MAO inhibitors. Make sure you tell your doctorif you have any other medical problems, especially:

• Alcohol abuse?Drinking alcohol while you are taking an MAOinhibitor may cause serious side effects

• Angina (chest pain) or
• Headaches (severe or frequent)?These conditions may interferewith warning signs of serious side effects of MAO inhibitors

• Asthma or bronchitis?Some medicines used to treat these conditionsmay cause serious side effects when used while you are taking an MAO inhibitor

• Diabetes mellitus (sugar diabetes)?These medicines may changethe amount of insulin or oral antidiabetic medication that you need

• Epilepsy?Seizures may occur more often

• Heart or blood vessel disease or
• Liver disease or
• Mental illness (or history of) or
• Parkinson's disease or
• Recent heart attack or stroke?MAO inhibitors may make the conditionworse

• High blood pressure?Condition may be affected by these medicines

• Kidney disease?Higher blood levels of MAO inhibitors may occur,which increases the chance of side effects

• Overactive thyroid or
• Pheochromocytoma (PCC)?Serious side effects may occur

Proper Use of This Medicine

Sometimes this medicine must be taken for several weeks before you begin tofeel better. Your doctor should check your progress at regular visits, especiallyduring the first few months of treatment, to make sure that this medicineis working properly and to check for unwanted effects.

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not takeit for a longer time than your doctor ordered.

MAO inhibitors may be taken with or without food or on a full or emptystomach. However, if your doctor tells you to take the medicine a certainway, take it exactly as directed.

Dosing?The dose of MAO inhibitors will be differentfor different patients. Follow your doctor's orders orthe directions on the label. The following information includes onlythe average doses of phenelzine and tranylcypromine. If your dose is different, do not change it unless your doctor tellsyou to do so.

The number of tablets that you take depends on the strength of the medicine.Also, the number of doses you take each day, the timeallowed between doses, and the length of time you take the medicine dependon the medical problem for which you are using an MAO inhibitor.

For isocarboxazid
• For oral dosage form (tablets):
  • For treatment of depression:
    • Adults?To start, 10 milligrams (mg) twice a day. Your doctormay increase your dose gradually as needed. However, the dose usually is notmore than 60 mg a day.
    • Children younger than 16 years of age?Use and dose must bedetermined by the doctor.

For phenelzine
• For oral dosage form (tablets):
  • For treatment of depression:
    • Adults?Dose is based on your body weight. To start, the usualdose is 1 milligram (mg) per kilogram (kg) of body weight (0.45 mg per pound)a day. Your doctor may decrease or increase your dose as needed. However,the dose usually is not more than 90 mg a day.
    • Children younger than 16 years of age?Use and dose must bedetermined by the doctor.
    • Older adults?To start, 15 mg in the morning. Your doctor mayincrease your dose gradually as needed. However, the dose usually is not morethan 60 mg a day.

For tranylcypromine
• For oral dosage form (tablets):
  • For treatment of depression:
    • Adults?To start, 30 milligrams (mg) a day. Your doctor mayincrease your dose gradually as needed. However, the dose usually is not morethan 60 mg a day.
    • Children younger than 16 years of age?Use and dose must bedetermined by the doctor.
    • Older adults?To start, 2.5 to 5 mg a day. The doctor may increaseyour dose as needed. However, the dose usually is not more than 45 mg a day.

Missed dose?If you miss a dose of this medicine, take it assoon as possible. However, if it is within 2 hours of your next dose, skipthe missed dose and go back to your regular dosing schedule. Do not doubledoses.

Storage?To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in otherdamp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be surethat any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

Whentaken with certain foods, drinks, or other medicines, MAO inhibitors can causevery dangerous reactions such as sudden high blood pressure (also called hypertensivecrisis). To avoid such reactions, obey the followingrules of caution:

• Do not eat foods that have a high tyramine content (most common infoods that are aged or fermented to increase their flavor), such as cheeses;fava or broad bean pods; yeast or meat extracts; smoked or pickled meat, poultry,or fish; fermented sausage (bologna, pepperoni, salami, and summer sausage)or other fermented meat; sauerkraut; or any overripe fruit. If a list of thesefoods is not given to you, ask your health care professional to provide one.
• Do not drink alcoholic beverages or alcohol-free or reduced-alcoholbeer and wine.
• Do not eat or drink large amounts of caffeine-containing food orbeverages such as coffee, tea, cola, or chocolate.
• Do not take any other medicine unless approved or prescribed by yourdoctor. This especially includes nonprescription (over-the-counter [OTC])medicine, such as that for colds (including nose drops or sprays), cough,asthma, hay fever, and appetite control; ?keep awake'' products; orproducts that make you sleepy.

This medicine will add to the effects of alcohol and other CNS depressants(medicines that slow down the nervous system, possibly causing drowsiness).Some examples of CNS depressants are antihistamines or medicine for hay fever,other allergies, or colds; sedatives, tranquilizers, or sleeping medicine;prescription pain medicine or narcotics; barbiturates; medicine for seizures;muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above whileyou are using this medicine.

Check with your doctor or hospital emergency room immediately if severe headache, stiff neck, chest pains, fast heartbeat, or nauseaand vomiting occur while you are taking this medicine. These may be symptomsof a serious side effect that should have a doctor's attention.

Do not stop taking this medicine without first checkingwith your doctor. Your doctor may want you to reduce gradually theamount you are using before stopping completely.

Dizziness, lightheadedness, or fainting may occur,especially when you get up from a lying or sitting position. Getting up slowly may help. When you get up from lying down, sit onthe edge of the bed with your feet dangling for 1 or 2 minutes. Then standup slowly. If the problem continues or gets worse, check with your doctor.

This medicine may cause blurred vision or make some people drowsy or lessalert than they are normally. Make sure you know howyou react to this medicine before you drive, use machines, or do anythingelse that could be dangerous if you are unable to see well or are not alert.

Antidepressants may cause some people to be agitated, irritable or displayother abnormal behaviors. It may also cause some people to have suicidal thoughtsand tendencies or to become more depressed. If you or your caregiver noticeany of these adverse effects, tell your doctor right away.

Before having any kind of surgery, dental treatment,or emergency treatment, tell the medical doctor or dentist in charge thatyou are using this medicine or have used it within the past 2 weeks.Taking MAO inhibitors together with medicines that are used during surgeryor dental or emergency treatments may increase the risk of serious side effects.

Your doctor may want you to carry an identification card stating that youare using this medicine.

For patients with angina (chest pain):

• This medicine may cause you to have an unusual feeling of good healthand energy. However, do not suddenly increase the amountof exercise you get without discussing it with your doctor. Too muchactivity could bring on an attack of angina.

For diabetic patients:

• This medicine may affect blood sugar levels. While you are usingthis medicine, be especially careful in testing for sugar in your blood orurine. If you have any questions about this, check with your doctor.

After you stop using this medicine, you must continueto obey the rules of caution for at least 2 weeks concerning food,drink, and other medicine, since these things may continue to react with MAOinhibitors.

Side Effects of This Medicine

Along with its needed effects,a medicine may cause some unwanted effects. Although not all of these sideeffects may occur, if they do occur they may need medical attention.

Stop taking this medicineand get emergency help immediately if any of the following side effectsoccur:

Symptoms of unusually high blood pressure (hypertensive crisis)

Chest pain (severe); enlarged pupils; fast or slow heartbeat; headache (severe); increased sensitivity of eyesto light; increased sweating (possibly with feveror cold, clammy skin); nausea and vomiting; stiff or sore neck

Check with your doctor as soon as possibleif any of the following side effects occur:

More common

Dizziness or lightheadedness (severe), especially when gettingup from a lying or sitting position

Less common

Diarrhea; fast or pounding heartbeat; swelling of feet or lower legs; unusual excitement or nervousness

Rare

Dark urine; fever; skin rash; slurred speech; sore throat; staggering walk; yellow eyes or skin

Symptoms of overdose

Anxiety (severe); confusion; convulsions (seizures); cool, clammyskin; dizziness (severe); drowsiness (severe); fast and irregular pulse; fever; hallucinations (seeing, hearing,or feeling things that are not there); headache (severe); high or low blood pressure; muscle stiffness; sweating; troubled breathing; trouble in sleeping (severe); unusual irritability

Other side effects may occurthat usually do not need medical attention. These side effects may go awayduring treatment as your body adjusts to the medicine. However, check withyour doctor if any of the following side effects continue or are bothersome:

More common

Blurred vision; decreased amount ofurine; decreased sexual ability; dizziness or lightheadedness (mild), especially when getting up from a lyingor sitting position; drowsiness; headache (mild); increased appetite (especially forsweets) or weight gain; increased sweating; muscle twitching during sleep; nausea; restlessness; shakinessor trembling; tiredness and weakness; trouble in sleeping

Less common or rare

Chills; constipation; decreased appetite; dryness of mouth

Other side effects not listed abovemay also occur in some patients. If you notice any other effects, check withyour doctor.

Additional Information

Once a medicine has been approvedfor marketing for a certain use, experience may show that it is also usefulfor other medical problems. Although these uses are not included in productlabeling, phenelzine and tranylcypromine are used in certain patients withthe following medical conditions:

• Headache
• Panic disorder

Other than the above information, there is no additional information relatingto proper use, precautions, or side effects for these uses.