Drugs – specific effects and risks

Drug classes

Drugs differ significantly in their effects and risks, but they fall broadly into four classes:

Stimulants, sometimes referred to as uppers, usually make users feel more alert and energized, but sometimes this can tip into over-confidence and aggression. They also boost vital functions such as heart rate and breathing rate, sometimes to a dangerous or even fatal level. Examples of stimulants include caffeine, nicotine, ecstasy/MDMA, cocaine and amphetamines such as crystal meth. 

Depressants, sometimes called downers, can make people feel relaxed, sleepy, or they may lose consciousness. Vital functions such as heart rate and breathing rate also slow down. Examples of depressants include alcohol, cannabis, benzodiazepines such as alprazolam (Xanax) and diazepam (Valium), and opioids. 

Psychedelics, also known as hallucinogens, distort sensory perception, so things that people are looking at or listening to appear different to how they would normally be. Someone’s mental and emotional state is likely to dictate how this will manifest – an individual who is in a negative headspace is at increased risk of a “bad trip”, which can be distressing. Examples of psychedelics include magic mushrooms and LSD. 

Dissociatives tend to cause a brief sense of euphoria which quickly fades into what can feel like an out of body experience, which may endure for minutes or hours, and at its most extreme can feel like the brain and body are completely separated from each other. Examples include nitrous oxide and ketamine. 

Drug classes are an oversimplification of what happens when someone takes something, and the Drugs Wheel illustrates this – not only are there many substances out there, but they can fall into more than one class and so have more than one set of effects (and therefore risks). The experience someone has depends not just on the substance they have taken, but a huge number of other factors. An added complexity is that drugs are known by many different names, some of which may seem obvious (plant or chemical names, for example) while others can be generic (such as pills) or may be slang or street names (for instance, mandy, whizz), and can be a source of confusion. 


What happens next?

Because a drug alters normal brain functioning and causes the mind and body to act differently to how would otherwise be the case, there is a need to recover afterwards. This is sometimes referred to as the comedown, and is basically the brain and body restoring themselves. This usually manifests as tiredness and low mood (which can tip into anxiety or fearfulness), and someone may feel like they are in the early stages of a cold or flu. This can happen with pretty much any substance, and may last hours or days, which is often longer than the experience the drug was taken to invoke. 

Tolerance can develop with some drugs, meaning someone needs to take increasingly higher doses in order to have a similar experience as previously was the case.  

Dependence can also develop, both physical, which involves the body’s chemistry changing so if the individual doesn’t get the drug they experience withdrawal symptoms, and psychological, particularly if the substance is being used as a coping mechanism. Someone who is dependent on a drug, which may be referred to as addiction, means the person feels a strong compulsion to keep taking it, which in turn removes the element of choice.  

Withdrawal can happen if someone reduces the amount of a drug they are taking, or stops altogether. The symptoms vary depending on the type and amount of drug being used, but can include agitation, mood changes, disturbed sleep, stomach problems such as diarrhoea and vomiting, headaches, and even hallucinations and seizures. Some drugs such as benzodiazepines and alcohol shouldn’t be stopped suddenly as the withdrawal symptoms can be so severe, it can be fatal.