Researchers have identified effective low doses for many common medications, including those for arthritis, high cholesterol, depression, hypertension, insomnia, and ulcers. While doctors rarely try the low-dose approach--in part because it requires extra monitoring at first to check its efficacy--it can eventually yield more efficient care as side effects decline and patient compliance improves. It’s particularly worth considering if you’re older, female, thin, or small; have had negative reactions to medication; or are unusually sensitive to either caffeine or alcohol, which might indicate greater sensitivity to medications in general.