TIL In 2010 Dave Grohl was admitted to hospital due to a drug overdose... He had consumed too much caffeine from coffee whilst recording a new album.

Coffee is not just caffeine; it contains monoamine oxidase inhibitors that greatly increase the potency and addictiveness of various other psychoactive substances - including caffeine.

Since these compounds inhibit both MAO-A and MAO-B, they increase the levels of the neurotransmitters serotonin, dopamine, noradrenaline and adrenaline. They do so by binding to the MAO enzymes, making them unable to break down the neurotransmitters.

This means that any drugs that release these neurotransmitters – i.e. pretty much any drugs – are going to become hugely more active! This is surprisingly uncommon knowledge.

Human monoamine oxidase enzyme inhibition by coffee and ß-carbolines norharman and harman isolated from coffee

Norharman and harman in instant coffee and coffee substitutes

Identification and occurrence of the bioactive ß-carbolines norharman and harman in coffee brews

Human monoamine oxidase is inhibited by tobacco smoke: beta-carboline alkaloids act as potent and reversible inhibitors.

Monoamine Oxidase Inhibition Dramatically Increases the Motivation to Self-Administer Nicotine in Rats

Transient behavioral sensitization to nicotine becomes long-lasting with monoamine oxidases inhibitors.

Harman in Alcoholic Beverages: Pharmacological and Toxicological Implications

Harman and norharman in alcoholism: correlations with psychopathology and long-term changes.

The role of beta-carbolines (harman/norharman) in heroin addicts

/r/todayilearned Thread Link - metro.co.uk