Symptoms and Complications
With substance use problems, people become dependent on the substance either physically, psychologically, or both.
Physical dependence involves becoming tolerant to a substance. This means that more of the drug or substance is needed to obtain the same effect. When people stop taking the substance, they suffer withdrawal symptoms that can include shaking, headaches, and diarrhea. Drug withdrawal can even be life-threatening. Mental or psychological problems such as depression and anxiety can also occur during drug withdrawal.
Some people can be physically dependent on a substance without being psychologically dependent on it, especially when a medication is being used for a valid medical condition.
Psychological dependence involves feeling that a substance is needed to feel good and function. With psychological dependence, people often crave the substance and will go to great lengths to acquire the substance to fulfill their craving. Substances that cause psychological dependence usually act on the brain and have one or more of the following effects:
- changes in mood (e.g., feeling "high")
- reduced anxiety
- feelings of superior abilities
- effects on the senses such as sight, hearing, etc.
There are many complications to substance use problems. They can cause physical problems such as liver disease, lung disease, heart disease, vitamin deficiencies, and brain damage. Some substances can cause birth defects and others can damage the immune system, which increases the risk of infections.
People using amphetamines can suffer from heart attacks, strokes, severe anxiety, and paranoia. Hallucinogens, because they distort reality, can make people temporarily psychotic or make them try things they can't realistically do, like flying. Conditions such as AIDS or hepatitis transmitted through shared, dirty needles are another complication. Overdoses of certain substances can even lead to death.
Other complications of substance use problems include social consequences such as damage to work, family, and personal relationships. Those who neglect their families create social problems for their spouses and children. They may commit criminal acts such as stealing to support their substance use problem. If they drive while under the influence of substances, death or injury to themselves or others can result. Some substances can alter the perception of reality and make people apathetic about work or school. If pregnant, a woman with a substance use problem may make her fetus physically dependent on the substance she's using.