What Are Illegal Drugs?

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What Are Illegal Drugs and How Do They Affect Us?

A drug is a mind-altering substance that affects neuropathways in the brain as well as the way in which the body functions. If a drug is classified as ‘illegal’ it means it is forbidden by law. Most illegal drugs are cut with other harmful chemicals, which makes them dangerous and unpredictable. Most drugs are divided into four main groups based on their effects. These groups are:

  • Stimulants 
  • Depressants 
  • Opium-related painkillers 
  • Hallucinogens


Stimulants are drugs that stimulate the central nervous system and speed up messages to the brain resulting in increased energy and confidence. Sometimes referred to as “uppers” due to their performance-enhancing effects, stimulant drugs produce intense feelings of euphoria due to a spike in the levels of dopamine in the brain. While you will feel an enhanced sense of well-being in the short term, long-term abuse of stimulant drugs can have devastating consequences. 

What Are Illegal Drugs

Abuse of these substances can cause you to experience:

  • Psychosis 
  • Paranoia 
  • Hyperactivity
  • Loss of appetite
  • Weight loss
  • Sweating
  • Jitteriness
  • Rapid heartbeat
  • Elevated blood pressure

Some of the most abused illegal stimulants include:

  • Cocaine
  • Crack cocaine
  • Ecstasy
  • Methamphetamine (Crystal meth)

Depressants (Sedatives)

Depressants are drugs that work by slowing down the body’s processes by depressing the central nervous system. This results in slower, reduced messages being sent to the brain. People taking depressants will find it difficult to focus and concentrate and may experience cognitive and visual impairment as well as delayed reaction times. 

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The most common side effects of depressant drugs include sedation, lack of cognitive function, relaxed muscles, low blood pressure, and respiratory depression.

Other potential side effects of abusing depressants include:

  • Dissociation
  • Respiratory depression
  • Seizures 
  • Drop in blood pressure 
  • Anxiety 
  • Depression 
  • Dizziness
  • Slurred speech
  • Fever
  • Sluggishness
  • Visual disturbances

Types of illegal depressants include:

  • GHB
  • Marijuana


Hallucinogens are drugs with the ability to completely alter your perception of reality. As their name suggests, these substances cause hallucinations and can change the way you see, hear, taste, and smell things. 

Most hallucinogens work in part, by temporarily interfering with the communication between the brain’s chemical systems and spinal cord, while other hallucinogens disrupt the action of the brain chemical serotonin to produce its effects.

What Are Illegal Drugs

Side effects of hallucinogens include:

  • Increased heart rate
  • Nausea
  • Warped perception of time 
  • Increased blood pressure
  • Respiratory rate 
  • Body temperature
  • Excessive sweating
  • Reduced appetite 
  • Potential weight loss
  • Dry mouth
  • Insomnia
  • Panic attacks
  • Paranoia 

However, these symptoms can vary depending on the type of hallucinogen taken. 

Examples of hallucinogens include:

What are illegal drugs

New Psychoactive Substances

New psychoactive substances, previously called ‘legal highs’ are drugs that contain one or more chemicals produced to mimic the effects of drugs like cocaine, cannabis, and ecstasy. 

Most synthetic drugs contain unknown chemicals, meaning there is not enough known about these drugs to predict their potency, their effects on people, or what happens when they’re used with other substances. This uncertainty means they are extremely dangerous and can cause serious damage to your health. 

New psychoactive drugs can be split into three categories based on the drugs they are designed to mimic. 

Stimulant NPS

Much like their non-synthetic counterparts, stimulant NSPs can lower inhibitions and make you feel overconfident. However, while they can bring about feelings of pleasure and euphoria in the short term, synthetic stimulants can also cause a host of unpleasant symptoms such as panic, confusion, paranoia, and even cause psychosis, all of which can increase the risk of causing serious harm to yourself and others. These stimulants can also put a huge strain on vital organs like the heart as well as the central nervous system and are also known to significantly lower the immune system. 

Downers or Sedative NPS

Synthetic sedatives can significantly impact concentration and reaction time. Much like non-synthetic downers, new psychoactive substances make you feel lethargic, forgetful, or physically unsteady, increasing the likelihood of an accident. These drugs can also cause unconsciousness, coma, and death, particularly when mixed with alcohol and other sedatives. Many users have also reported developing anxiety once they stop taking synthetic NPSs and experiencing severe withdrawal symptoms. 

Synthetic Cannabinoids

While cannabis users rarely suffer any life-threatening side effects as a result of their drug use, synthetic cannabinoids are extremely dangerous. When taken in excess, you are at risk of seizures, accelerated heart rates, high blood pressure, excessive sweating, and dehydration.

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