(phenelzine sulfate)

Prescribing Information
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CLINICAL PHARMACOLOGY

CLINICAL PHARMACOLOGY

Monoamine oxidase is a complex enzyme system, widely distributed throughout the body. Drugs that inhibit monoamine oxidase in the laboratory are associated with a number of clinical effects. Thus, it is unknown whether MAO inhibition per se, other pharmacologic actions, or an interaction of both is responsible for the clinical effects observed. Therefore, the physician should become familiar with all the effects produced by drugs of this class.

Pharmacokinetics

Absorption

Following a single 30 mg dose of NARDIL® (2 × 15 mg tablets), a mean peak plasma concentration (Cmax) of 19.8 ng/mL occurred at a time (Tmax) of 43 minutes postdose.

Metabolism

NARDIL® is extensively metabolized, primarily by oxidation via monoamine oxidase. After oral administration of 13C6-phenelzine, 73% of the administered dose was recovered in urine as phenylacetic acid and parahydroxyphenylacetic acid within 96 hours. Acetylation to N2-acetylphenelzine is a minor pathway.

Elimination

The mean elimination half-life after a single 30 mg dose is 11.6 hours. Multiple dose pharmacokinetics have not been studied in man.

Medication Guide

MEDICATION GUIDEANTIDEPRESSANT MEDICINES, DEPRESSION AND OTHER SERIOUS MENTAL ILLNESSES, AND SUICIDAL THOUGHTS OR ACTIONS

Medication Guide Antidepressant Medicines, Depression and other Serious Mental Illnesses, and Suicidal Thoughts or Actions

Read the Medication Guide that comes with you or your family member's antidepressant medicine. This Medication Guide is only about the risk of suicidal thoughts and actions with antidepressant medicines. Talk to your, or your family member's, healthcare provider about:

  • all risks and benefits of treatment with antidepressant medicines
  • all treatment choices for depression or other serious mental illness

What is the most important information I should know about antidepressant medicines, depression and other serious mental illnesses, and suicidal thoughts or actions?

1.
Antidepressant medicines may increase suicidal thoughts or actions in some children, teenagers, and young adults within the first few months of treatment.
2.
Depression and other serious mental illnesses are the most important causes of suicidal thoughts and actions. Some people may have a particularly high risk of having suicidal thoughts or actions. These include people who have (or have a family history of) bipolar illness (also called manic-depressive illness) or suicidal thoughts or actions.

How can I watch for and try to prevent suicidal thoughts and actions in myself or a family member?

  • 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.
  • Keep all follow-up visits with the healthcare provider as scheduled. Call the healthcare provider between visits as needed, especially if you have concerns about symptoms.

Call a healthcare provider right away if you or your family member has any of the following symptoms, especially if they are new, worse, or worry you:

  • thoughts about suicide or dying
  • attempts to commit suicide
  • new or worse depression
  • new or worse anxiety
  • feeling very agitated or restless
  • panic attacks
  • an extreme increase in activity and talking (mania)
  • trouble sleeping (insomnia)
  • new or worse irritability
  • acting aggressive, being angry, or violent
  • acting on dangerous impulses
  • other unusual changes in behavior or mood

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

What else do I need to know about antidepressant medicines?

  • Never stop an antidepressant medicine without first talking to a healthcare provider. Stopping an antidepressant medicine suddenly can cause other symptoms.
  • Antidepressants are medicines used to treat depression and other illnesses. It is important to discuss all the risks of treating depression and also the risks of not treating it. Patients and their families or other caregivers should discuss all treatment choices with the healthcare provider, not just the use of antidepressants.
  • Antidepressant medicines have other side effects. Talk to the healthcare provider about the side effects of the medicine prescribed for you or your family member.
  • Antidepressant medicines can interact with other medicines. Know all of the medicines that you or your family member takes. Keep a list of all medicines to show the healthcare provider. Do not start new medicines without first checking with your healthcare provider.
  • Not all antidepressant medicines prescribed for children are FDA approved for use in children. Talk to your child's healthcare provider for more information.

This Medication Guide has been approved by the U.S. Food and Drug Administration for all antidepressants.

October 2008

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