Drug dynamics and kinetics (Effectiveness and Safety) Text: London

Drug Interactions

When two or more drugs are taken in the same general time period, they may interact in ways that are good or bad. Together they may be more effective in treating a problem, or they may in­crease the number or severity of adverse reac­tions. Drug interactions may occur between pre­scription and nonprescription (over-the-counter) drugs. If someone is receiving care from more than one doctor, each doctor needs to know all of the drugs being taken. Preferably, people should obtain all their prescription drugs from the same pharmacy, one that maintains a complete drug profile for each patient. The pharmacist can then check for the possibility of interactions. People should also consult their pharmacist when se­lecting over-the-counter drugs (for example, lax­atives, antacids, and cough or cold remedies), particularly when they're also taking prescription drugs.

Although many people don't consider alcohol adrug, it affects body processes and is often re­sponsible for drug interactions. Doctors or phar­macists can provide answers to questions about possible alcohol and drug interactions.

Drug interactions aren't always bad. For exam­ple, some drugs used for treating high blood pressure are prescribed in combination to reduce the side effects that could develop if a single drug were prescribed at a higher dose.

To assist health care practitioners in developing a safe and effective treatment plan, people must be sure that their doctor, nurse, or pharmacist has the following information:

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  What medical problems they have
  
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  What drugs (both prescription and nonprescription) they have taken in the previous few weeks
  
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  Whether they are allergic to or have had an unusual reaction to any drug, food, or other substance
  
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  Whether they have special diets or food restrictions
  
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  Whether they are pregnant or plan to become pregnant or are breastfeeding
  

Drug Abuse

Through the ages, drugs have been enormously beneficial in relieving suffering and in preventing and treating diseases. However, to some people, the word drug means a substance that alters the brain's function in ways considered pleasurable. There has always been a dark side to the discov­ery and use of drugs, especially those that alle­viate anxiety or alter mood and behavior in ways that satisfy people's emotional needs. Drug abuse-the excessive and persistent use of mindaltering substances without medical need-has accompanied the appropriate medical use of drugs throughout recorded history. Commonly abused drugs include alcohol, marijuana, co­caine, barbiturates, benzodiazepines, methaqualone, heroin and other narcotics, amphetamines, LSD (lysergic acid diethylamide), and PCP (phertcyclidine).