Help is here. You are not alone
Table of content
Table of content
All About Recovery
Facebook Group • 2213 members
There's always clouds before the rainbows. Join many others who are going through the same thing as you and see proof that it can get better.

Can Drugs Permanently Damage the Brain?

Can Drugs Permanently Damage the Brain?
Written by Seth Fletcher on August 17, 2020
Last update: February 26, 2024

Drug use can cause a variety of effects on vital organs such as the brain and the heart. Some of these effects may be short-term, which means that they typically disappear soon after use. On the other hand, long-term effects last long after the drug use has taken place, sometimes for months or even years. 

Unfortunately, there are permanent drug effects that stay with the user forever and are irreversible despite attempts to return to a healthier state. Many of the permanent damage caused by drugs occur in the brain, but the drug use effects can also occur in other parts of the body. 

For example, cocaine attacks the cardiovascular system and causes permanent damage to the heart and blood vessels. Consider starting drug addiction treatment as soon as possible to ward off or avoid the worsening of the permanent effects of drugs on the body. 


Why is the brain vulnerable to damage by drug use?

Recreational drug use and chronic drug addiction can cause permanent damage to the brain’s structure and its delicate chemical balance. The brain is like a computer that controls a person’s body. Disruption of this system can cause serious effects. Each brain cell works with other brain cells to create pathways in the brain. These pathways play a role in controlling specific functions of the body.

Moreover, brain cells release tiny amounts of chemicals when they connect with other brain cells. These brain chemicals, in the right quantity, are a form of communication to ensure that the brain activates the appropriate function. 

Too much or too little of these chemicals in the brain can have a substantial negative impact on one’s body and mental health. Drugs often increase, reduce or completely block off certain chemicals within the brain, causing a brain chemical imbalance. These brain chemical imbalances can produce irreversible effects on one’s body and mental health. 

Furthermore, a healthy brain protects itself from toxic molecules and organisms that may be found in the person’s blood. It is the mechanism called the blood-brain-barrier (BBB) that provides this protection. Certain drugs, such as methamphetamine, can disrupt the BBB function, which may allow neurotoxic agents to enter the brain. This could explain why methamphetamine is highly toxic to the brain and causes permanent damage to the brain cells.

Drug addiction can also cause brain cells to die. When brain cells die, they do not grow back. Brain cell death affects the brain pathways as well as the overall balance of the brain chemicals. The more brain cells that die, the higher the risk that there will be a negative effect on the body or mind. Doctors refer to this as neurotoxicity; “neuro” meaning the brain and nerves, and “toxicity” meaning toxic.

Chronic or high dose drug use is notorious for its potential to cause permanent brain cell death. This is particularly concerning for unborn babies and youth as the brain is in development until one reaches approximately 25 years of age. 

Consider starting a drug addiction program as soon as the problem has been identified to avoid serious complications. One of the goals of drug addiction treatment is to restore the natural brain chemical balance of the user. This process comes with withdrawal symptoms as the brain adjusts to the new, healthier chemical changes. It is important to have a drug addiction support team to help the user adjust to their healthier state.


Why is the heart vulnerable to damage by drug use?

In a healthy state, various chemical signals within the body can indicate to the heart that it should relax or work faster and harder. With the use of drugs, some of these chemical signals can be either overly enhanced or reduced, thus causing the heart to act abnormally. This abnormal heart activity can last for a short or long duration and sometimes can be reversible. However, some of these effects can lead to serious consequences, including death. 

Drug use by injection causes additional heart problems. Improper and unsanitary injections can result in collapsed veins and bacterial infections within the blood vessels and the heart itself. A drug addiction program can help the user to understand the risks better and learn strategies to gain control of their lives.


Permanent effects of chronic or high-dose drug use specific per substance

Each addictive substance can produce a range of irreversible effects on one’s body and mental health, depending on the way that it acts on the brain and other organs. The irreversible effects per substance mentioned below may not occur to all drug users. Still, all drug users are putting themselves at a higher risk of these effects with continued usage. 



  • Chronic use or high doses can modify the brain’s structure, chemistry and function 
  • Increased likelihood of developing schizophrenia (withdrawal from reality, inaccurate perception) or Parkinson’s disease (tremors, muscle rigidity, slow movements)
  • A significant loss in brain white matter (the tissue around the brain cells that facilitates communication between the brain cells)


  • Stroke, heart attack or aneurysms which may result in permanent damage or even death
  • Permanent damage to blood vessels in the brain


  • Kidney failure

Diseases spread by blood (drug injection)

  • HIV
  • Hepatitis B
  • Hepatitis C


  • Premature ageing
  • Development of “meth mouth”; extensive cavities, tooth enamel erosion
  • Structural damage to the jaw bone

Use during pregnancy – impact on the baby 

  • Increased risk of cardiac anomalies
  • Increased risk of cleft lip and palate



  • Shrinkage of brain
  • Changes to the brain structure and chemical balance
  • Damage to the part of the brain that controls cognitive, emotional and behavioural functioning

Use during pregnancy – impact on the baby

  • Spontaneous abortion

Diseases spread by blood (drug injection)

  • HIV
  • Hepatitis B
  • Hepatitis C



  • Irreversible brain damage


  • Acute respiratory distress syndrome which can lead to death

Diseases spread by blood

  • Severe sepsis that can lead to death
  • HIV
  • Hepatitis B
  • Hepatitis C



  • Scarring and increased thickening of the heart muscle
  • Inflammation of the heart muscle 
  • Uncontrolled cell death in the heart tissues
  • Stiff arteries
  • High blood pressure that can lead to a heart attack
  • Heart attack which can lead to death
  • Life-threatening irregular heartbeat

Use during pregnancy – impact on the baby

  • Increased risk of cardiac anomalies 
  • Cardiac arrest
  • Sudden death syndrome (SIDS) 
  • Stillbirth

Diseases spread by blood

  • HIV
  • Hepatitis B
  • Hepatitis C


Brain: Use during adolescence

  • Brain structure changes (including the area responsible for memory and judgement)
  • Loss of grey matter in some regions of the brain
  • Loss in cognitive function



  • Brain cell structural changes
  • Brain chemistry imbalance

Damaged organs

  • Kidney, liver, pancreas, heart, brain

Other risks

  • Colorectal cancers

The Canadian Centre for Addictions (CCFA) is here to help

The Canadian Centre for Addictions (CCFA) offers a full range of quality services that give our visitors flexible therapy ad counselling for drug and alcohol addiction. Contact us now, and ask about our addiction program.


Sources used for the article

  • American Heart Association. Illegal Drugs and Heart Disease. Sept 30
  • Dhein, Stefan. Different Effects of Cannabis Abuse on Adolescent and Adult Brain. Pharmacology. July 6 2020. DOI: 10.1159/000509377
  • Garland Brown, Kate and Capili, Bernadette. Opioid Use Disorder: Pathophysiology, Assessment, and Effective Interventions. AJN. June 2020. Vol. 120, No. 6
  • Ghuran, A. et al. Cardiovascular complications of recreational drugs. BMJ Volume 323. 1 September 2001. Pp.464-6.
  • Gilloteaux, Jacques and Ekwedlike, Nelson N. Cocaïne Atrial Purkinje Fiber Damage. J Ultrastructural Pathology. Volume 34, 2010. Issue 2. 
  • Grigorakos, Leonidas et al. Outcome of acute heroin overdose requiring intensive care unit admission. J Opioid Manag. May-Jun 2010;6(3):227-31. Doi: 10.5055/jom.2010.00021.
  • Huang, Sihong et al., White Matter Abnormalities Based on TBSS and its Correlation With Impulsivity Behavior of Methamphetamine Addicts. Frontiers in Psychiatry. May 2020. Volume 11. Article 452.
  • Kivisaari, Reetta et al. Cerebral measurements and their correlation with the onset age and the duration of opioid abuse. J Opioid Manag. Nov-Dec 2010; 6(6):423-9. Doi: 10.5055/jom.2010.0040
  • Martins, Tania et al. Methamphetamine transiently increases the blood-brain-barrier permeability in the hippocampus: Role of tight junction proteins and matrix metalloproteinase-9. Brain Research. Volume 1422, 9 September 2011, Pages 28-40.
  • Nasimul Islam, Mohammed et al. Histopathological studies of cardiac lesions after long term administration of methamphetamine in high dosage – Part II. Leg Med (Tokyo). 2009 Apr;11 Suppl 1:S147-50.
  • Pabst, Andreas et al. Meth Mouth – A Growing Epidemic in Dentistry? Dent. J. 2017, 5, 29; doi:10.3390/dj5040029.
  • Pan, Chi-syuan et al. Alcohol use disorder tied to development of chronic kidney disease: A nationwide database analysis. PLOS One 13(9): e0203410. September 6, 2018.
  • Pereira, Pedro A. et al. Effects of chronic alcohol consumption and withdrawal on the cholinergic neurons of the pedunculopontine and lerodorsal tegmental nuclei of the rat: An unbiased stereological study. NeuroToxicology. Volume 76, January 2020, Pages 58-66.
  • Richards JR, Le JK. Cocaine Toxicity. [Updated 2020 Jun 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from:
  • Singla, Ankush et al. Is Chronic Opioid Abuse Associated With Cerebral Atrophy? An Observational Study. Indian J Crit Care Med. 2020 Apr; 24(4): 276-280.
  • U.S. Department of Health and Human Services. Substance Abuse and Mental Health Services Administration. Substance Abuse Treatment: Addressing the Specific Needs of Women. A Treatment Improvement Protocol TIP 51. 2009.
  • Wen, Di et al. Effects of Molecular Hydrogen on Methamphetamine-Induced Neurotoxicity and Spatial Memory Impairment. Frontiers in Pharmacology. July 2019. Volume 10. Article 823. 
Certified Addiction Counsellor

Seth brings many years of professional experience working the front lines of addiction in both the government and privatized sectors.

More in this category: