Physical Side Effects of Drug Addiction

Physical Side Effects of Addiction

The mental side effects of drug abuse and addiction are well documented – depression, anxiety, mood swings, broken-down relationships, and more are all commonly associated with dependency on drugs or alcohol.

But what about the physical effects of drugs?

One thing is for sure – different drugs have different effects on the body, and when it comes to illegal substances that are illegal, these effects are never going to be positive.

It’s important to be aware of these effects though, as they can help us, both to get the message if our drug abuse is going too far and to notice the telltale signs in other people, especially our loved ones.

If you are suffering with drug addiction, contact us to see how we can help you. Rehab or detoxing are usually the most recommended action.

What Do Drug Addicts Look Like?

Physical Effects of Taking Drugs

It goes without saying that different drugs affect the human body in different ways, but effects can vary from person to person too.

A person’s size, body weight, tolerance, other drugs in the system and other factors can all come into play, and this is without going into the fact that some black market drugs can be cut with other unknown and potentially dangerous substances.

It’s also not uncommon for your mood or even personality to entirely change while under the influence of drugs.

This could be a giggly euphoria that can be seen as a positive in a social setting, but it can also go the complete opposite way, making you irritated, aggressive and unable to control yourself.

While there are many different forms of illegal drugs available, there are three main types that affect the human body in similar ways:


Stimulants do exactly what it says on the tin – they stimulate our central nervous systems, which involves making messages between the body and brain move more quickly. 

This is similar to our natural fight or flight response and can cause side effects such as:

  • Agitation
  • Constant sweating
  • Dehydration
  • Loss of appetite
  • Insomnia
  • High blood pressure

Drugs that are stimulants (to varying degrees) include:


Depressants are essentially the direct opposite of stimulants – they slow down the central nervous system and the messaging between the brain and body.

This can cause side effects as simple as feeling sleepy or loss of inhibitions, but they can also lead to some of the most dangerous examples of physical effects of drugs on the body, for example:

  • Slowed heart rate
  • Loss of motor skills
  • Unconsciousness
  • Coma
  • Death

Even small amounts of depressants are potentially lethal due to the risks of drink driving or operating machinery under the influence. The most common depressants include:


Hallucinogens operate on a completely different scale when it comes to the physical side effects of drugs. Instead of depressing or stimulating the central nervous system, they actually change your perception of reality and can cause a variety of different hallucinatory experiences.

Side effects can include:

  • Visual hallucinations or “trips”
  • Auditory hallucinations
  • Euphoria
  • Jaw clenching
  • Paranoia

Drugs that are considered hallucinogens include:

  • LSD (Acid)
  • Magic mushrooms
  • Ketamine
  • DMT
  • To a lesser extent, cannabis

Behavioural Changes

Of course, while all of the above information might help you to avoid drug use yourself, it’s also important to be able to notice it in others, so that you are able to help a loved one should they get into their own addiction issues.

While different drugs provide different side effects as we’ve already discussed, there are some that can be considered universal signs of drug addiction and therefore are always worth looking out for.

These include:

  • A sudden change in school grades – especially if previously doing well and suddenly failing for no discernible reason
  • A sudden change in the friendship group
  • Loss of interest in hobbies
  • Mood swings or agitation
  • Lack of energy for chores or constant lethargy
  • Bloodshot eyes
  • Constant giggling or laughing
  • Financial issues or asking to borrow money

Spotting Drug Addiction in Teenagers

Spotting drug abuse or addiction in teenagers can be especially difficult because many of the above signs of drug addiction are potentially normal for teens.

For example, mood swings, agitation and lack of energy for chores can all be a normal part of puberty and the teenage experience. Similarly, issues like changing groups of friends, financial issues or asking to borrow money can simply be a result of alcohol use or changing opinions.

Despite this, the teenager’s body and brain are still developing, which makes this the most important time to be aware of these signs.

Getting Help for Drug Addiction

If you or a loved one are suffering from drug addiction, the most important thing is that you get professional help as early as possible to reduce your chances of doing severe damage or worse.

Here at Serenity Centres, we run the UK’s most respected rehabilitation clinics with locations all over the country.

We also offer home detox programmes so you can experience all of the same benefits and support while overcoming addiction from the comfort of your own home.

We can offer:

  • GP consultations
  • Medication to help reduce withdrawal symptoms
  • Access to experienced doctors, nurses and therapists
  • Advice and guidance on local private and NHS resources
  • A 24/7 helpline with friendly, non-judgemental experts who are waiting to advise you, some of whom have overcome drug addiction themselves
  • Cognitive behavioural therapy sessions
  • Support groups and talks with people who have overcome similar issues
  • Nutritionists and personal trainers to keep you distracted and healthy
  • Holistic treatments such as acupuncture, yoga, and more

So what are you waiting for? Call us now on 0800 118 2892 to begin your journey to freedom!

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