Isocarboxazid treats depression. This medication interacts with tyramine which is found in some cheeses and other foods which can result in dangerously high blood pressure. Avoid these foods/drinks.

Isocarboxazid Overview

Reviewed: August 9, 2013

Isocarboxazid is a prescription medication used to treat depression. Because of its potentially serious side effects, it is often used only after other antidepressants haven't worked. Isocarboxazid belongs to a group of drugs called monoamine oxidase (MAO) inhibitors. It works by increasing the levels of certain natural chemicals in the brain that affect your mood and help maintain mental balance.

Isocarboxazid comes in tablet form. It is usually taken 2 to 4 times daily, with or without food.

Common side effects include nausea, dry mouth, and dizziness. Isocarboxazid can cause drowsiness. Do not drive or operate heavy machinery until you know how it affects you.

Patient Ratings for Isocarboxazid

How was your experience with Isocarboxazid?

First, a little about yourself

Tell us about yourself in a few words?

What tips would you provide a friend before taking Isocarboxazid?

What are you taking Isocarboxazid for?

Choose one
  • Other
  • Depressive Disorder

How long have you been taking it?

Choose one
  • Less than a week
  • A couple weeks
  • A month or so
  • A few months
  • A year or so
  • Two years or more

How well did Isocarboxazid work for you?

Did you experience many side effects while taking this drug?

How likely would you be to recommend Isocarboxazid to a friend?

Isocarboxazid Cautionary Labels


Uses of Isocarboxazid

Isocarboxazid is a prescription medication used to treat depression, when other medications have failed.

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

Isocarboxazid Brand Names

Isocarboxazid may be found in some form under the following brand names:

Isocarboxazid Drug Class

Isocarboxazid is part of the drug class:

Side Effects of Isocarboxazid

Serious side effects have been reported. See "Drug Precautions" section.

Common side effects include:

  • dry mouth
  • dizziness
  • diarrhea
  • headaches
  • nausea
  • constipation
  • insomnia
  • drowsiness
  • low blood pressure when standing or sitting up
  • difficulty urinating
  • shakiness

This is not a complete list of isocarboxazid side effects. Ask your doctor or pharmacist for more information.

Isocarboxazid Interactions

Tell your doctor about all of the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

  • 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
  • medications containing alcohol (Nyquil, elixirs, others)

This is not a complete list of isocarboxazid drug interactions. Ask your doctor or pharmacist for more information.

Isocarboxazid can remain in your body for 2 weeks after you stop taking it. Tell your doctor or pharmacist that you recently stopped taking isocarboxazid before you start taking any new medications.

Isocarboxazid Precautions

Serious side effects have been reported with isocarboxazid including:

Hypertensive crisis, a life threatening increase in blood pressure. This sometimes fatal side effect can result from taking MAO inhibitors like isocarboxazid with certain drugs and foods (see "Drug Interactions" and "Food Interactions" sections). Symptoms include:

  • headaches
  • stiff or sore neck
  • nausea
  • vomiting
  • palpitations
  • sweating, sometimes with fever and cold, clammy skin
  • either fast or slow heart beat
  • chest pain
  • chest tightness
  • dilated pupils

Get medical help right away if you experience these symptoms.

Severe headaches. If you have frequent headaches, talk to your doctor before starting isocarboxazid as headaches are one of the first symptoms of a hypertensive crisis and you may miss this warning sign.

Suicidal thoughts or behavior. Antidepressants may increase suicidal thoughts or actions in some children, teenagers, and young adults within the first few months of treatment. 

  • Pay close attention to any changes, especially sudden changes, in mood, behaviors, thoughts, or feelings. This is very important when an antidepressant medicine is started or when the dose is changed.
  • Call the healthcare provider right away to report new or sudden changes in mood, behavior, thoughts, or feelings.

Low blood pressure, especially when getting up from a lying position.

Worsening of seizures in people with epilepsy. Before taking isocarboxazid, tell your doctor if you have epilepsy.

Do not take isocarboxazid if you:

  • are allergic to any ingredient in isocarboxazid
  • have heart disease
  • have high blood pressure
  • have a type of adrenal tumor known as pheochromocytoma
  • have a history of a stroke
  • have had a transient ischemic attack (TIA)
  • have had bleeding in the brain
  • are going to have surgery 
  • have liver disease
  • are taking drugs that should not be taken during treatment with isocarboxazid

Isocarboxazid can cause drowsiness. Do not drive or operate heavy machinery until you know how it affects you.


Isocarboxazid Food Interactions

Tyramine is a naturally occurring compound found in some cheeses and other foods that may cause dangerously high blood pressure in people taking monoamine oxidase inhibitors (MAOIs) like isocarboxazid.

You should avoid eating very large amounts of foods containing high amounts of tyramine such as:

  • cheese (particularly strong or aged varieties)
  • sour cream
  • Chianti wine
  • sherry
  • beer (including non-alcoholic beer)
  • liqueurs
  • pickled herring
  • anchovies
  • caviar
  • liver
  • canned figs
  • raisins
  • bananas
  • avocados (particularly if overripe)
  • chocolate
  • soy sauce
  • sauerkraut
  • the pods of broad beans (fava beans)
  • yeast extracts
  • yogurt
  • meat extracts
  • meat prepared with tenderizers
  • dry sausage

Some of the signs and symptoms of dangerously high blood pressure (hypertensive crisis) are:

  • severe headache
  • vision problems
  • confusion
  • stupor (mental numbness)
  • coma
  • seizures
  • chest pain
  • unexplained nausea or vomiting
  • stroke-like symptoms (sudden numbness or weakness - especially on one side of the body)

Get emergency medical help if you experience these symptoms.


Inform MD

Before taking isocarboxazid tell your doctor about all of your medical conditions. Especially tell your doctor if you:

  • have heart, liver, or kidney disease
  • have high blood pressure
  • have had a stroke or heart attack
  • have pheochromocytoma
  • have frequent headaches
  • have or have family members with bipolar disorder
  • have tried to commit suicide
  • have epilepsy
  • have a scheduled surgery or radiology procedure
  • have hyperthyroidism
  • drink alcohol
  • are pregnant or breastfeeding

Tell your doctor about all of the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Isocarboxazid and Pregnancy

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Isocarboxazid falls into category C. No studies have been done in animals, and no well-controlled studies have been done in pregnant women. Isocarboxazid should be given to a pregnant woman only if clearly needed.


Isocarboxazid and Lactation

Tell your doctor if you are breastfeeding or plan to breastfeed.

It is not known if isocarboxazid crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using isocarboxazid.


Isocarboxazid Usage

  • Take isocarboxazid exactly as prescribed.
  • Isocarboxazid comes in tablet form and is taken 2 to 4 times a day.
  • It can be taken with or without food.
  • If isocarboxazid upsets your stomach, try taking it with food.
  • If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of isocarboxazid at the same time.

Isocarboxazid Dosage

Take isocarboxazid exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The isocarboxazid dose your doctor recommends will be based on the following:

  • other medical conditions you have
  • other medications you are taking
  • how you respond to this medication 

​The recommended starting dose is one tablet (10 mg) of isocarboxazid twice daily.

If tolerated, dosage may be increased by increments of one tablet (10 mg) every 2 to 4 days to achieve a dosage of four tablets daily (40 mg) by the end of the first week of treatment.

Dosage can then be increased by increments of up to 20 mg/week, if needed and tolerated, to a maximum recommended dosage of 60 mg/day.

Daily dosage should be divided into two to four dosages.

After maximum clinical response is achieved, an attempt should be made to reduce the dosage slowly over a period of several weeks without jeopardizing the therapeutic response. Beneficial effect may not be seen in some patients for 3 to 6 weeks.


Isocarboxazid Overdose

If you take too much isocarboxazid, call your local Poison Contol Center or seek emergency medical attention right away.

Other Requirements

  • Store at room temperature between 15°C and 30°C (59°F - 86°F).
  • Keep this and all medications out of the reach of children.

Isocarboxazid FDA Warning

Suicidality and Antidepressant Drugs

Antidepressants increased the risk compared to placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies with Major Depressive Disorder (MDD) and other psychiatric disorders. Anyone considering the use of isocarboxazid or any other antidepressant in a child, adolescent or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults beyond age 24; there was a reduction in risk with antidepressants compared to placebo in adults aged 65 and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Isocarboxazid is not approved for use in pediatric patients.

Pooled analyses of short-term (4 to 16 weeks) placebo-controlled trials of 9 antidepressant drugs (SSRIs and others) in children and adolescents with major depressive disorder (MDD), obsessive compulsive disorder (OCD), or other psychiatric disorders (a total of 24 trials involving over 4400 patients) have revealed a greater risk of adverse events representing suicidal thinking or behavior (suicidality) during the first few months of treatment in those receiving antidepressants. The average risk of such events in patients receiving antidepressants was 4%, twice the placebo risk of 2%. No suicides occurred in these trials.