31st January 2024

Background

Stimulants are another substance classification commonly used recreationally. They include ecstasy (MDMA), amphetamines and cocaine. Some amphetamines, such as dexamphetamine, have been prescribed for Attention Deficit Hyperactivity Disorder (ADHD). They enhance the release of serotonin, dopamine and norepinephrine  (monoamine) neurotransmitters by blocking reuptake, resulting in increased levels within neural synapses. The excess release of these neurotransmitters causes the euphoria commonly experienced when they are ingested, increasing the risk of dependence. However, after prolonged use, levels of these neurotransmitters become depleted, causing long-term effects on cognition and mood.

MDMA reaches peak concentration in the blood approximately 2 hours post-ingestion and undergoes hepatic metabolism; however, it has an extensive half-life, which may account for the longevity of symptoms.

Amphetamines were first marketed as a treatment for nasal congestion; however, due to their high abuse potential, very few today remain medically licensed, e.g., for the treatment of narcolepsy or Parkinson’s disease. They can be injected, smoked or taken orally.

Cocaine is sourced from the coca plant and can be ingested orally, nasally or injected. The effects last up to one hour after consumption, and it has a short half-life. Topically, cocaine can have an anaesthetic effect as well as cause vasoconstriction, but if enough is absorbed systemically, alpha and beta adrenoreceptors may be stimulated, which causes tachycardia.