| Beneficial interactions: Some drug-drug interactions are utilized for their beneficial effects so drug combinations are used to improve the therapeutic objective or to decrease adverse events: • Example; Trimethoprim and sulfamethoxazole-a combination antibiotic for increased efficacy in urinary tract infections. • Amoxicillin and clavulanate potassium-a combination containing a beta-lactamase inhibitor (clavulanate) to inhibit the breakdown of amoxicillin. • Hydrochlorothiazide and enalapril containing a combination diuretic and antihypertensive to minimize potassium excretion. • Probenecid inhibits renal tubular secretion of penicillin, therefore prolonging the plasma half- life of the antibiotic. • Interactions between propofol and other intravenous agents may be synergistic or additive. Interactions between propofol and opioids are more marked during surgery than during induction of anesthesia. Propofol interferes with opioid metabolism to increase circulating concentrations of opioid, the main objective of combining propofol with other drugs is to reduce propofol and opioid dosage so that the same anesthetic effect can be achieved without compromising cardiovascular stability. Beneficial consequences of lower dosages include shortened recovery times and fewer unpleasant opioid-related side effects. • Taking a copper supplement may enhance the anti-inflammatory effects of NSAIDs while reducing their gastrointestinal side effects. One study found that copper chelates of various anti- inflammatory drugs increased the anti-inflammatory activity of the medications. Some nutritionally oriented doctors recommend that people taking NSAIDs also take 2–3 mg/day of copper. • Combining 300 IU of vitamin D per day with estradiol plus a progestin led to greater improvement in bone density than treatment with estradiol/progestin alone. |
Drug Interactions
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