Monoamine oxidase inhibitors (MAOIs) are a category of antidepressants that act on an amine called monoamine oxidase which affects neurotransmitters such as serotonin, norepinephrine, and dopamine. MAOIs retard the action of monoamine oxidase which metabolizes these neurotransmitters, thereby increasing the levels of these neurotransmitters. Increased levels of these neurochemicals help lower depression in a person.

MAO inhibitors sometimes may give rise to situations which are life-threatening in nature, such as abrupt increase in blood pressure which may prove fatal. MAOIs have serious side effects with other medicines, food items and beverages. These hazardous side effects may not appear immediately, but take effect after many hours of taking the certain foods and beverages.

People, who are on MAOI medication, should not take any other medication unless it is prescribed by a medical professional. These avoidable medications include: sleep pills and products; treatment drugs for cold, cough, asthma or fever, nasal sprays and drops; diet control pills; and drugs used for keeping a person awake and alert. The other medications that interact with MAOIs and give serious side effects are: Medications used during surgical interventions, orthodontic procedures, and emergency treatments.

Side Effects of MAOIs

Discontinue MAOIs immediately and get urgent medical help if any of the following side effects of severe hypertension appear in a person.

Acute pain in the chest; acute pain in the head; rigidity in neck area; dilated pupils; irregular heart beat; temporary loss of eyesight; heightened perspiration with temperature or cold; nausea and vomiting.

The common side effects of MAOIs: Indistinct vision; less urination; sexual impairment; mild giddiness under mild exertion; sleepiness; cephalalgia; increased propensity to eat, particularly starch items; heightened perspiration; involuntary muscle twitching during sleep; nausea; impatience; trembling; exhaustion and weariness; sleep disorders. The less common side effects of MAOIs are: Chills; costiveness; lack of interest in food; mouth dehydration.

MAOIs seriously affect people with their daily chores and also cause side effects to those who use other medications for treatment of some illnesses.

Sleepiness: MAO inhibitors cause a person’s vision to become fuzzy and indistinct. One becomes sleepy and feels sedated. When driving a vehicle or working on machinery, clear eye-sight, focus, and alertness are necessary. Persons using MAOIs should keep this side effect in mind whenever they attempt to do such activities.

Diabetes: Monoamine oxidase inhibitors affect blood sugar levels in a person who is a diabetic. These inhibitors may affect the quantum of insulin or oral antidiabetic medication that one takes. Testing sugar levels in blood and urine is needed before starting MAOI medications.

Giddiness: MAOI medications may cause a person feel giddy even with mild exertions such as when trying to get up and stand quickly. This the common side effect of these inhibitors. It may be due to lowering of blood pressure. It may cause muscle weakness, sweating, nausea, breathlessness, and dizziness. This effect may stabilize after some time. If the problem persists, reduce the potency and increase the frequency of medication on doctor’s advice.

Prior to surgery: Before undergoing any surgical interventions, orthodontic procedures or any emergency treatments, it is needed to tell the surgeons about current usage of MAOI medications. Even people who stopped medications two weeks earlier should make it a point to inform doctor. MAOIs and anesthesia are potent combinations that cause a serious drop in blood pressure. Surgeries requiring general anesthesia are to be avoided.

Sexual Impairment: MAOIs, like with other antidepressants, cause side effects regarding sexual functions. Fluoxetine is known to cause delayed orgasm. But these problems may eventually subside .  

The Tyramine Effect

MAOI users should be cautious with their diet, otherwise they will face severe side effects with their medication. An amino acid called tyramine in the body regulates blood pressure. Foods and food items, beverages, etc., that contain high levels of tyramine will further enhance inhibitor drug effect that may bring catastrophic consequences for the drug user. Increased levels of tyramine in the body will cause high blood pressure which may lead to stroke or cerebral hemorrhage.

Tyramine is present in some foods. Bacterial action on proteins also causes tyramine in over-ripe and aged foods and food items. Tyramine content also depends on type of processing, preservatives used, and storage methods. It is better to eat fresh foods and food items.

Take only fresh meat, fish, eggs, poultry, milk and milk products. Avoid high alcohol content beverages, fermented soy products, broad beans, and sausages.