There’s a long list of prescribed medications, as well as over-the-counter drugs and recreational substances and supplements, that can interfere with effective treatment for hypertension. In addition to estrogen-containing drugs and NSAIDS, the list includes widely used medicines like antidepressants and oral steroids such as cortisone; substances like nicotine, alcohol and cocaine; herbal supplements like licorice or ginseng; and, of course, salt. Caffeine, too, can raise blood pressure over the short-term in some people.

When doctors fail to ask patients what else they may be taking, using or consuming that can affect blood pressure — or if patients neglect to mention all of the over-the-counter and herbal remedies and prescription drugs they take — patients may be prescribed an unnecessary or more potent blood pressure drug that may have bothersome side effects.

Dr. Anderson said that doctors were “taught to screen patients initially for other drugs being taken that can raise blood pressure, but patients are not necessarily rechecked for such drug use over time.” He said that it was important for doctors to take good medical histories, including what might have changed in patients’ lives since their blood pressures were last under control.

“Maybe there was a change in diet that caused a quick rise in blood pressure,” Dr. Anderson said. “For example, some patients are very salt-sensitive,” he said. “Along with age and weight, it’s the strongest predictor of high blood pressure over time.” Changing just one frequently consumed high-salt food, like pizza, cured meats or canned soup, may be enough to lower the risk of hypertension.

Complicating matters is that people’s reactions to various substances, like the commonly prescribed S.S.R.I. antidepressants, are “very idiosyncratic,” he explained. “A particular S.S.R.I. may have a high impact on blood pressure in some patients but not others.”

For patients with hypertension who need to take a drug that can raise blood pressure, Dr. Anderson advised using a home blood pressure monitor. A sudden rise in blood pressure after starting a new drug can help alert the prescribing doctor to the need to switch to an alternative remedy if one is available.

Even if you’ve had normal blood pressure for five or more decades, there’s a 90 percent chance that you’ll develop hypertension as you get older, which makes it all the more important to modify risks like dietary salt and excess weight while you’re still healthy. Even a modest weight loss of 10 pounds can both reduce the risk of developing hypertension and lower blood pressure in overweight people who already have this condition.