Monoamine oxidase inhibitors (MAOIs) are a type of antidepressant that doctors sometimes prescribe for depression, panic disorders, and social anxiety.
This article explores how MAOIs work and which dietary habits are important for people taking this type of drug.
Below, we also describe other precautions, which types of MAOI are available, and what side effects to look out for.
MAOIs are a type of antidepressant medication. As
Nowadays, doctors tend to only prescribe this type of drug when other medications have not been effective. This is because taking MAOIs requires important dietary restrictions and because these drugs can cause significant side effects.
MAOIs affect the balance of certain chemicals in the brain. These chemicals are called neurotransmitters, and they are essential for brain function.
Serotonin is one neurotransmitter among many, and scientists also believe that depression could involve disturbances in the levels of other neurotransmitters.
- brain-derived neurotrophic factor
Monoamine oxidases are enzymes that breaks down
MAO-A is most involved in breaking down serotonin.
As MAOIs block this enzyme, the levels of serotonin, norepinephrine, and dopamine increase. When this occurs in the brain of someone with depression, their symptoms may improve, as a result.
There are several types of drugs in this class.
Some that have received approval from the
Some of these medications come in pill form, while others come as adhesive patches that a person places on their skin. For example, selegiline is sold as a skin patch under the brand name Emsam.
Tyramine is a type of chemical compound called a monoamine. Other types are neurotransmitters such as dopamine, serotonin, and norepinephrine.
Taking MAOIs can increase tyramine levels in the body. If someone taking an MAOI eats foods with high quantities of tyramine, levels of this chemical in the body can rise dangerously high.
High levels of tyramine can cause:
- high blood pressure
- brain bleeds, if the person’s blood pressure is very high
Which foods should a person avoid?
The body produces little tyramine, but eating and drinking foods and beverages rich in tyramine will raise its level in the body.
High-tyramine foods and drinks
- cheese, such as cheddar and feta
- fermented vegetables, such as kimchi and sauerkraut
- cured or salt-dried meats
- pickled or salt-dried shrimp or fish
- beer and wine
- soy sauce
- Worcestershire sauce
- some fresh produce, like avocado, grapes, and beets
Also, tyramine occurs in higher concentrations in older foodstuffs. For this reason, anyone taking MAOIs should avoid any pickled, fermented, and overripe food.
MAOIs can interact with other drugs.
It is important that anyone taking an MAOI does not also take a selective serotonin reuptake inhibitor (SSRI). Combining the two can lead to serotonin syndrome, which involves serotonin levels rising too high.
Among the medications that can cause serotonin syndrome, MAOIs cause the
Serotonin syndrome can be fatal. For this reason, anyone taking an MAOI who experiences any of the following symptoms should contact a healthcare professional right away.
Symptoms of serotonin syndrome include:
- agitation and restlessness
- nausea and vomiting
- a rapid heart beat
- a high body temperature
- tremors and muscle jerks
- muscle rigidity
- overactive reflexes
- dilated pupils
- flushed skin
- increased bowel sounds
It is also dangerous to take more of an MAOI than was prescribed or to mix this type of drug with another antidepressant.
In addition, doctors warn that anyone who has taken an MAOI the past
MAOIs can cause side effects, and
- dry mouth
Additionally, MAOI skin patches can sometimes cause skin reactions.
One 2018 study describes how antidepressant drugs can increase the likelihood of suicidal thoughts, behavior, and related death.
SSRIs were the most likely to correlate with these effects.
The authors of the study report that, in comparison, tricyclic antidepressants (TCAs) and noradrenergic and specific serotonergic antidepressants (NaSSAs) were very rarely correlated with these factors.
And MAOIs were even less likely than TCAs and NaSSAs to correlate with suicidal thoughts, behavior, and related death.
Doctors sometimes prescribe MAOIs to help treat depression, panic disorders, and social anxiety. The drugs block monoamine oxidase, which is an enzyme that breaks down neurotransmitters in the brain.
However, because MAOIs have many side effects, and because new treatments are available, medical experts tend to prescribe MAOIs as a last resort.
A person taking MAOIs needs to have a limited diet to help prevent levels of tyramine in their body from rising. Also, it is important to never combine an MAOI and an SSRI, as doing so can lead to serotonin syndrome, which can be fatal.