Over $78 billion in prescription and over-the-counter (OTC) drugs are produced each year in the United States alone. Although most people use these medications properly, a significant number do not. They might take them without a doctor's prescription, use more than prescribed, or take them for reasons other than those that the drugs were prescribed for.
In 1998, the Substance Abuse and Mental Health Services Administration's (SAMHSA) National Household Survey on Drug Abuse showed that over 20 million people over the age of 12 reported having used one or more psychotherapeutic drugs (stimulants, sedatives, tranquilizers, and analgesics available through prescription) for non-medical purposes at some time in their lives. Stimulants, analgesics, and tranquilizers were the most widely used drugs of abuse that fit this category.
Psychotherapeutic drugs are abused because they directly affect the brain and central nervous system (CNS), producing desired effects. 
What Are Some Of The Most Common Medications?
Amphetamines and caffeine
These are stimulants used primarily to delay the onset of mental and physical fatigue. Students studying long hours for exams, athletes who feel the drugs will improve their performance, and workers who want to stay awake on the job often use stimulants. These drug compounds are often found in diet pills which, if misused, can lead to anorexia nervosa. Anorexia nervosa is a pathological loss of appetite thought to be psychological in origin that is manifested in extreme dieting and excessive thinness. Caffeine is also found in many beverages, pain medications, and allergy and cold remedies.
Unusually high doses, or excessive use of stimulants over long periods of time can lead to anxiety, hallucinations, severe depression, or physical and psychological dependence. From a strong stimulant such as cocaine to nicotine in cigarettes and caffeine in coffee and cola drinks, stimulants are an intimate part of our lives.
Some of the most widely used analgesics, available in both prescription and over-the-counter forms, include:
- Aspirin - The most common analgesic used today to treat fever, arthritis and pain; possible side effects can include nausea, heartburn or development of bleeding ulcers. Aspirin prevents stomach upset. Reye's syndrome may develop if aspirin is given to children with the flu or chicken pox. This disease is characterized by vomiting, swelling of the brain and liver, difficulty with mental functioning, and can often lead to death. People with liver damage should also avoid using aspirin.
- Aceteminophen (Tylenol) - is used to treat aches, pains and fevers and is generally free from side effects. Large doses or overuse of this drug may cause rashes, fevers or changes in blood composition. People with kidney or liver problems should consult a doctor before using acetaminophen.
- Ibuprofen (Motrin, Advil, Nuprin) - is used to relieve pain associated with arthritis, menstrual cramping and discomfort, fever, and muscle strains. Possible side effects might include upset stomach, dizziness, drowsiness, headache, or ringing in the ears. Overuse of this drug may lead to confusion, tingling in hands and feet, and vomiting.
These are prescription medications used to treat depression, a disease affecting over 15 million Americans. Some of the original drugs of this group were Nardil, Tofranil and Elavil. Although not technically an antidepressant, lithium, which used to treat manic depression, is often in this group. The side effects of prolonged and excessive use of these drugs are excessive urination or thirst, diarrhoea, vomiting, drowsiness, dizziness or muscle weakness. Some newer antidepressants that show great promise in treating this disease are Wellbutrin, Prozac and Zoloft. The incidence of side effects with these seem to be less than with the previously used medications.
Sedative-Hypnotics and Tranquilizers
Benzodiazepines are the most widely prescribed tranquilizers and sleep-inducing medications. Drugs used to treat anxiety and tension are Valium, Xanax, Ativan, and Tranxene. Drugs used for sleeping are Dalamine, Restotril and Halcion. Possible side effects include drowsiness, poor coordination or light-headedness. Overuse of these drugs can lead to respiratory difficulties, sleeplessness, coma and even death.
They are less commonly prescribed medications used to treat anxiety and insomnia. Some examples are Seconal, Phenopbarbital and Nembutal. If improperly used, these drugs can cause an individual to feel depressed or experience respiratory difficulties.
Cough and Cold Preparations
Colds are caused by viruses and typically last 7 to 10 days. Most cold preparations are designed to treat specific cold symptoms and provide temporary relief from discomfort. Most widely used cold remedies include the following: • Antihistamines and Decongestants - These medications are typically used to relieve the itchy, watery eyes and reduce congestion due to allergies, colds and flu. They can cause drowsiness or excitability. • Antitussives and Expectorants - Antitussives are cough suppressants used to treat painful, persistent coughs. Expectorants are used to help clear mucous from the respiratory system. Both medications may contain alcohol and some may contain narcotics, such as codeine, to relieve pain and induce sleep. Some may be addictive. Young people may abuse these medications for the effects derived from alcohol use, as the alcohol content in some OTC preparations may be as high as 40 percent.
They are among the most widely misused and abused over the counter medications. Use of laxatives should be restricted to short term-use for constipation, since chronic use leads to dependency.
Misuse of prescription and OTC drugs can often lead to psychological and physical dependence. People use increased amounts of drugs to ensure a sense of well-being while treating unrelated illnesses or health problems, or for non-medical purposes.
Many medications contain alcohol and narcotics such as codeine, which can be addictive and life-threatening. Use of alcohol, a depressant, with some prescription and over-the-counter drugs may inhibit or increase the drug's effectiveness and cause a loss of coordination. Combining OTC drugs with some prescription drugs can cause the similar effects, or even more harmful types of reactions.
References  Quoted from The National Clearinghouse for Alcohol and Drug Information.
For more information about drugs or prescription medications contact:
The National Clearinghouse for Alcohol and Drug Information P.O. Box 2345 Rockville, MD 20847-2345 1-800-729-6686 TDD 1-800-487-4889 Hablamos Espanol