One of the challenges in today's health care setting is keeping up with the wealth of knowledge that is required to safely prescribe medications and, if you are a consumer, to safely take them. Drug-drug interactions occur when the administration of a drug results in decreased effectiveness or increased toxicity of other drugs that are also being taken. Drug-food interactions occur when the effectiveness of the drug is decreased, or the toxicity increased, because of its interaction with foods. Drug use increases significantly with age, and the most commonly prescribed drugs are cardiovascular, sleep, anxiety, analgesic, and musculoskeletal medications.
Drug interactions occur by a variety of mechanisms.
Pharmacokinetic means the journey of a drug through your body - from the time you swallow a pill until the time that it is eliminated in the feces or in the urine. Another pharmacokinetic interaction involves a drug that can slow down or speed up the rate by which your body eliminates other drugs. This interaction can result in the accumulation of terfenadine and result in heart beat abnormalities. Also, interactions involving drugs with cumulative therapeutic effects, such as anti-anxiety medications taken at the same time with sleep medications, can cause excessive drowsiness and sleepiness. Other interactions involving drugs with cumulative side effects, such as antihistamines taken with a muscle relaxant, may cause excessive sedation.