Brain & Behaviour Health

How drugs work?

Written by new sensation

Written by Numan Mughal



Drugs are the chemicals that affect the body’s natural way of responding. These chemicals change the person’s physical as well as mental condition. Some drugs are prescribed for any illness whereas some are taken for recreational pursuit, and are illegal in almost all over the world.

Drugs which affect the person’s mental condition are called psychoactive drugs, whether they are taken for recreational or medical purposes. Psychoactive drugs, which affect the person mental condition, also affect the way he behaves and most of them are responsible for impairment of memory.


Depressants are the drugs which slow down the heart rate, and the way brain and spinal cord respond. The person’s alertness level is also decreased finally feeling of “high” and doziness. Examples include marijuana, heroin and tranquilizers.

Stimulants increase the respiration and breathing rate, and increase the alertness level and also give strong euphoric (state of wellbeing) feelings. Drugs are highly addictive for example caffeine, cocaine etc.

Hallucinogens affect in such a way that a person sees, smells and feels the things which aren’t present. Hallucinogens take the person to ecstasy (a state of extreme high, joyful and happiness). The examples are methylenedioxymethamphetamine or MDMA and cannabis.


If you feel pain, central nervous system (CNS) is responsible for the sensation of pain and give instructions to body how to minimize it? How drugs affect brain functions is a long story? In this article only brief information is compiled to save the readers time. The drugs must possess the ability to pass from the body to the brain. In the brain the drugs interfere with the working of neurotransmitters and affect the way brain cells interact with each other and send messages to the whole body. The drugs simply interfere with CNS and cease/over activate some connections of central nervous system with the body temporarily, so person could feel pain is ceased. This is soothing but at the expense of your neural health. Drugs are not only used to reduce pain but also used to get rid from emotional states which are irresistible to one’s mind capacity. Some drugs are addictive because of their strong effects of ecstasy and being in highness. Besides of their pain relieving and other soothing effects there are some adverse short term and long term side effects.

Short term affects include the anxiety disorders in which the person has panic attacks with increased heart rate and trembling and sweats. Drug induced psychosis is another effect in which person feels things that aren’t present. These effects also include mood disorders in which the patient feels abrupt mood swings, depressed, restlessness and tiredness as well.

Long term effects of drug use include ecstasy; a state of being in highness in which one can feel him/herself disconnected from this world and may have different feelings like false affection, depression; is medical illness in which one can feel sadness, loss of interest in his/her favorite activities, difficulty in being focused and decision making and schizophrenia; a mental disorder in which one can hear the voices others can’t, misbelieves, false or confused thinking. In addition to the person’s relationships, social and university life is also affected. The risks of unemployment and violence are increased. The damage to internal organs, risk of infectious diseases  and loss of memory temporarily or permanently are also included in long term effects.


Emotions and memory are complexly entangled and, as we know different drugs affect our brain and emotions differently, ultimately causing impairment and loss of our memory. Most drugs when intoxicated highly cause mood swings, cognitive functions, disruption in brain activity resulting in impaired memory or memory loss.

In order to know how drugs involved in memory loss it is necessary to know about different brain parts and their functions. Neurons (nerve cells) are fundamental unit of central nervous system (CNS). Brain consisted of three parts; brain stem, cerebrum and cerebellum. Cerebrum is largest part of brain and controls cognitive functions, decision making, storage of memory and lot of other functions. Cerebellum controls body balance, attention, language, emotions (pleasure & fear etc) and particularly motor function. Brian stem controls heart rate, breathing, body temperature and digestion etc. Brain connects with the whole body through nerve cells. In short all body functions are controlled and kept in balance with the help of nervous system.

Drugs That May Cause Memory Loss

About 10 types of drugs are directly or indirectly involved in memory loss in humans. Types of drugs involving memory loss are followings; antianxiety, Cholesterol, antiseizure, antidepressant, narcotic painkillers, Hypertension, Sleeping aids, Incontinence, antihistamines and Parkinson’s drugs.

Marijuana or tetrahydrocannabinol (cannabinoid receptors), heroin & opioids (opioid receptors), cocaine & methamphetamine (Dopaminic receptors), benzodiazepines (beta adrenergic receptors) and ecstasy (methylenedioxymethamphetamine) all work in somewhat similar manner but using their respective receptors. All drugs are involved in reduction in sensation of pain by stimulating GABA production (a neurotransmitter; responsible for inhibition of pain, anxiety and stress). In addition to GABA, marijuana and heroin also increases dopamine and serotonin levels. Dopamine is neurotransmitter which is responsible to keep cells in appropriate state to meet our needs resulting in the feeling of pleasure, wellbeing, high. Marijuana and heroin influence more adversely in during childhood when the neural connections and synapsis are not fully developed in limbic system. These drugs particularly disturb the neural connections and synapsis which are responsible for converting short term memory to long term memory in hippocampus. When these connections are ceased these drugs prevent to make new short term memories results eventually in memory loss. Cocaine is responsible for building dopamine overwhelming pool eliciting strong effects of ecstasy, state of joyful and happiness. In case of cocaine overdose blood vessels of the brain constricts lowering brain activity resulting in impaired memory.

Hallucinogens and methylenedioxymethamphetamine both over activate receptors to produce increased levels of dopamine and serotonin preventing pain sensation and overdose of these drugs also responsible for ceased neural cell connections and short term memory buildup problem.


It is concluded from above given information that collectively, either addictive or prescriptional drugs all drugs have pain reliving effects by over activating different kind of pathways which control and reduce the pain sensation and give strong feeling of being in extreme joyful and happiness state. This state of joyfulness takes a person into unconsciousness by disrupting some neural connections preventing from building new memories ultimately loss of memory and impaired brain functions. Which affect one’s personal and social life and could increase the risks of unemployment in society.


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new sensation

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