pronounced as (eye soe kar box' azid)

Brand Name(s): Marplan®

Why is this medicine prescribed?

Isocarboxazid is used to treat depression in people who have not been helped by other antidepressants. Isocarboxazid is in a class of medications called monoamine oxidase (MAO) inhibitors. It works by increasing the amounts of certain natural substances in the brain that help maintain mental balance.

Are there other uses for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Isocarboxazid comes as a tablet to take by mouth. It is usually taken between two and four times a day. Take isocarboxazid at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take isocarboxazid exactly as directed.

Swallow the tablets with water or another liquid. If you are unable to swallow the tablets, you can crumble them and swallow the crumbled tablets with food or liquid.

Isocarboxazid may be habit-forming. Do not take a larger dose, take it more often, or take it for a longer period of time than prescribed by your doctor.

Your doctor will probably start you on a low dose of isocarboxazid and gradually increase your dose, not more often than once every 2 to 4 days at first, and then not more often than once every week. After your symptoms improve, your doctor will probably gradually decrease your dose of isocarboxazid.

Isocarboxazid is used to treat depression but does not cure it. It may take 3 to 6 weeks or longer before you feel the full benefit of isocarboxazid. Tell your doctor if your symptoms do not improve during the first 6 weeks of your treatment with isocarboxazid. If your symptoms do improve during your treatment, continue to take isocarboxazid. Do not stop taking isocarboxazid without talking to your doctor.

What special precautions should I follow?

Before taking isocarboxazid,

  • tell your doctor and pharmacist if you are allergic to isocarboxazid, any other medications, or any of the inactive ingredients in isocarboxazid tablets. Ask your pharmacist for a list of the inactive ingredients.
  • do not take isocarboxazid if you are taking or plan to take any of the following prescription or nonprescription medications: certain other antidepressants such as amitriptyline (Elavil), amoxapine (Asendin),clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), imipramine (Tofranil), maprotiline, nortriptyline (Aventyl, Pamelor), protriptyline (Vivactil), trimipramine (Surmontil), and selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft);amphetamines such as amphetamine (in Adderall), benzphetamine (Didrex), dextroamphetamine (Dexedrine, Dextrostat, in Adderall), and methamphetamine (Desoxyn); antihistamines; barbiturates such as pentobarbital (Nembutal), phenobarbital (Luminal), and secobarbital (Seconal); bupropion (Wellbutrin, Zyban); buspirone (BuSpar); caffeine (No-Doz, Quick-Pep, Vivarin); cyclobenzaprine (Flexeril); dextromethorphan (Robitussin, others); diuretics ('water pills'); duloxetine (Cymbalta); ephedrine (in cough and cold medications, formerly available in the US as an ingredient in dietary supplements); epinephrine (Epipen); guanethidine (Ismelin; not commercially available in the US); levodopa (Laradopa, in Sinemet); medications for allergies, asthma, cough, and cold symptoms, including nose drops; medications for high blood pressure, mental illness, anxiety, pain, or weight loss (diet pills); medications for seizures such as carbamazepine (Tegretol); methyldopa (Aldomet); methylphenidate (Concerta, Metadate, Ritalin, others); other MAO inhibitors such as phenelzine (Nardil), procarbazine (Matulane), tranylcypromine (Parnate), and selegiline (Eldepryl, Emsam, Zelapar); reserpine (Serpalan); sedatives; sleeping pills; tranquilizers; and medications containing alcohol (Nyquil, elixirs, others). Tell your doctor if you have recently taken any 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: disulfiram (Antabuse); doxepin cream (Zonalon); insulin; oral medications for diabetes; and medications for nausea. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • you should know that isocarboxazid may remain in your body for 2 weeks after you stop taking the medication. Tell your doctor and pharmacist that you have recently stopped taking isocarboxazid before you start taking any new medications during the first 2 weeks after you stop taking isocarboxazid.
  • 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),tyrosine, or tryptophan.
  • tell your doctor if you or anyone in your family has or has ever had schizophrenia (a mental illness that causes disturbed thinking, loss of interest in life, and strong or unusual emotions). Also tell your doctor if you have ever used street drugs or overused prescription medications and if you have or have ever had a head injury; hyperactivity; headaches; high blood pressure; chest pain; a heart attack; a stroke or mini-stroke; pheochromocytoma (tumor on a small gland near the kidneys); seizures; diabetes; or liver, kidney, thyroid, or heart disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking isocarboxazid, call your doctor.
  • you should know that isocarboxazid may make you drowsy. Do not drive a car, pilot an airplane, operate machinery, climb ladders, or work in high places until you know how this medication affects you.
  • you should know that isocarboxazid 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 isocarboxazid. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
  • if you are having surgery, including dental surgery, or any x-ray procedure, tell the doctor or dentist that you are taking isocarboxazid.
  • remember that alcohol can add to the drowsiness caused by this medication. Do not drink alcohol while you are taking isocarboxazid.

What special dietary instructions should I follow?

You may experience a serious reaction if you eat foods that are high in tyramine during your treatment with isocarboxazid. 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 isocarboxazid. Follow these directions carefully. Ask your doctor or dietitian if you have any questions about what you may eat and drink during your treatment.

What should I do if I forget to take a dose?

Take the missed dose as soon as you remember it. However, if it has been more than 2 hours since you were supposed to take the dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What should I do in case of overdose?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • fast heartbeat
  • dizziness
  • fainting
  • blurred vision
  • nausea
  • coma (loss of consciousness for a length of time)
  • seizures
  • slowed breathing
  • slowed reflexes
  • fever
  • sweating

What side effects can this medicine cause?

Isocarboxazid may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • dry mouth
  • constipation
  • diarrhea
  • weakness
  • extreme tiredness
  • forgetfulness
  • decreased sexual ability
  • frequent, painful, or difficult urination

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:

  • headaches
  • fast or pounding heartbeat
  • chest pain
  • sweating
  • fever
  • chills
  • cold, clammy skin
  • dizziness
  • tightness in the chest or throat
  • stiff or sore neck
  • nausea
  • vomiting
  • fainting
  • blurred vision
  • sensitivity to light
  • wide pupils (black circle in the middle of the eye)
  • yellowing of the skin or eyes
  • uncontrollable shaking of a part of the body
  • sudden jerking of a part of the body
  • seizures
  • numbness, burning, or tingling in the arms or legs

Isocarboxazid may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( ) or by phone (1-800-332-1088).

What should I know about storage and disposal of 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).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( ) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will check your blood pressure often and will order certain lab tests to check your body's response to isocarboxazid.

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.

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