Drug addiction is a brain disease. Although initial drug use might be voluntary, drugs of abuse have been shown to alter gene expression and brain circuitry, which in turn affect human behaviour. Once addiction develops, these brain changes interfere with an individual’s ability to make voluntary decisions, leading to compulsive drug craving, seeking and use.{{more}}

The impact of addiction can be far reaching. Cardiovascular disease, stroke, cancer, HIV/AIDS, hepatitis, and lung disease can all be consequences of drug abuse. Some of these effects occur when drugs are used at high doses or after prolonged use; however, some may occur after just one use.

Drug abuse not only weakens the immune system, but is also linked to risky behaviours, like needle sharing and unsafe sex. The combination greatly increases the likelihood of acquiring HIV-AIDS, hepatitis and many other infectious diseases. People engage more in risky sexual activities under the influence of drugs and so many sexually transmitted diseases can be contracted. Unwanted pregnancy can also result in these circumstances.

Researchers have found a connection between the abuse of most drugs and adverse cardiovascular effects, ranging from abnormal heart rate to heart attacks. Injection drug use can also lead to cardiovascular problems, such as collapsed veins and bacterial infections of the blood vessels and heart valves.

Drug abuse can lead to a variety of respiratory problems. Smoking cigarettes, for example, has been shown to cause bronchitis, emphysema and lung cancer. Marijuana smoke may also cause respiratory problems. The use of some drugs may also cause breathing to slow, block air from entering the lungs or exacerbate asthma symptoms.

All drugs of abuse act on the brain to produce their euphoric effects; however, some of them also have severe negative consequences in the brain, such as seizures, stroke, and widespread brain damage that can impact all aspects of daily life. Drug use can also cause brain changes that lead to problems with memory, attention and decision-making. Chronic use of some drugs of abuse can cause long-lasting changes in the brain, which may lead to paranoia, depression, aggression, and hallucinations.

Some drugs may cause kidney damage or failure, either directly or indirectly from dangerous increases in body temperature and muscle breakdown. Chronic use of some drugs, such as heroin, inhalants and steroids, may lead to significant damage to the liver.

In addition to the effects various drugs of abuse may have on specific organs of the body, many drugs produce global body changes, such as dramatic changes in appetite and increases in body temperature, which may impact a variety of health conditions. Withdrawal from drug use also may lead to numerous adverse health effects, including restlessness, mood swings, fatigue, changes in appetite, muscle and bone pain, insomnia, cold flashes, diarrhoea, and vomiting.

If you are suffering from drug abuse or you know of someone with this problem, it may be time to seek professional help in order to protect your health.

Dr Rosmond Adams is a medical doctor and a public health specialist.

He may be emailed at adamsrosmond@gmail.com