Throughout your life (and there’s more of it to come) you’ve been told again and again of the effects of drugs and how taking them can end up turning you into a corpse. You’ve also been told about how this is all rubbish. So which sources of information do you trust – your school teachers or your stoner friends? This article aims to provide you with another source of information, obtained from psychologists, neuroscientists and pharmacologists, allowing you to make an informed decision about what you yourself want to do in possible situations where you’ll be offered drugs.
Alcohol – Alcohol molecules readily cross the blood-brain barrier and act on multiple neurotransmitters. Alcohol acutely inhibits the main excitatory transmitter of the nervous system at a particular receptor subtype, and this leads to the memory loss associated with intoxication in the short-term. As well as this, alcohol also modulates the action of the nervous system’s main inhibitory transmitter – both by increasing its release and enhancing the function of its receptor proteins. Alcohol also acts on the dopaminergic system that, when hijacked by drugs, are responsible for addictive behaviours.
Cannabis – The psychoactive ingredient in ‘weed’ is THC – Δ9-tetrahydrocannabinol. THC binds to a type of receptor that is expressed throughout the brain, and so has a wide range of effects –reduced locomotor activity, hypothermia, catalepsy and hypoalgesia. Reactions to the drug are dose-dependent, and despite what many people say, research utilising both clinical and ‘normal’ populations have shown that both tolerance and dependence can result from chronic cannabinoid exposure.
Cocaine – After neurotransmitter molecules are released by neurons, they are taken back up by specialised transporter proteins so that their effects on the next neuron are ended. Cocaine works by blocking the action of the transporter responsible for taking up dopamine, and so more dopamine is left in between neurons. This is responsible for the reinforcing effects of cocaine, which make it a highly addictive drug.
Ketamine – Ketamine is a highly reinforcing drug that induces a state of dissociative anethesia – a ‘K-hole’. It exerts its effect by blocking the action of a certain type of glutamate receptor that is highly expressed throughout the cortex, and this is responsible for the cognitive deficits induced by use. Ketamine users are often found to exhibit white or grey matter abnormalities following chronic exposure to the drug, which underlies an increase in delusional thinking. If taken, ketamine must never be mixed with alcohol – the result can be fatal (it is a horse-version of a sleeping pill, after all).
MDMA/Mandy/Molly/Ecstasy – The feel good effects of this ‘love drug’ arise from the mass increase in release of serotonin upon drug administration. This can lead to feelings of oneness with everyone around you, euphoria and even mild hallucinations. However, the human brain does not naturally release serotonin in such large bursts naturally, and so the mechanisms tasked with correcting this did not evolve to do this as rapidly as other neurotransmitters. This leads to the ‘come down’ depressive state, which can last any time between one day and one week depending on how often the drug is taken. As well as this, MDMA has a neurotoxic effect which can lead to permanent changes in serotonergic systems in the brain.
Obviously if you or a friend decide to dabble with these, and other, substances, no one is going to stop you. But the main thing to remember is that to make the informed decision to take a drug, you need to know what it is going to do your body and your brain. As with everyone, moderation is key, and because of the fact that most drugs are sold impure, what has worked for you one time may not necessarily produced the same effects the next!