Sacred Entheogens and MAOI's
Monoamine oxidase inhibitors (MAOIs) are drugs/substances which inhibit the activity of monoamine oxidase enzymes. In modern medicine, these are primarily prescribed for the treatment of depression and can be particularly effective in treating atypical depression. They are also used in the treatment of social anxiety, Parkinson's disease & several other disorders. Interestingly, many synthetic MAOI's are actually based on or derived from naturally occurring biologic organisms.
So what exactly is the function of MAO/MAOI's?
Monoamine Oxidases (MAO) are a group of enzymes which are naturally produced by the body. They are primarily responsible for breaking down natural monoamines found in our diet, but also responsible for deactivating monoamine neurotransmitter receptors. A few examples of monoamine (MA) neurotransmitters are Serotonin, Dopamine, and Norepinephrine. MAO's mechanism of action consists of breaking the bond that neurons form with the above mentioned monoamine neurotransmitters. This allows the neuron to form new bonds with other neurotransmitters, therefore making MAO crucial in regulating emotion, arousal, and memory, along with many other neural, emotional, and cognitive functions.
Monoamine Oxidase Inhibitors (MAOI's) are substances that have the ability to inhibit the production of MAO. Due to the chemistry of most Psychoactive molecules (which bond with monoamine neurotransmitter receptors), MAOI's have the ability to lengthen & potentiate a psychedelic experience. Under "normal" circumstances the psychedelic experience lasts for as long as it takes the body to produce enough MAO to break the bonds that are formed between the psychedelic molecule and MA neurotransmitters. However, when a psychedelic/entheogen is taken simultaneously with an MAOI (which inhibits the production & activity of MAO) the result is an experience which can last up to 2x as long, and be much more intense.
While Ancient humans could not have known the pharmacodynamics behind Monoamine Oxidase Inhibitors, they nevertheless knew that certain plants could be used to potentiate a psychedelic experience.
Many of these natural MAOI's (including Syrian Rue, Kava root, & Banisteriopsis Caapi) have a long history of human use due to their ability to both lengthen and potentiate the effects of many psychedelic/entheogenic substances. The most popular example of an MAOI/Psychedelic combination is undoubtedly Ayahuasca, which combines Banisteriopsis Caapi (a natural MAOI) with Psychotria Virdis (a plant high in psychoactive DMT).