If you choose to take diet pills for weight loss, it is in your best interest to speak to your doctor first. He will take into consideration any medications you currently take, along with the possible drug interactions these medications may have with prescription diet pills. He considers any health conditions you have as well. Some diet pills, such as diethylpropion and phenylpropanolamine, may increase your blood pressure, according to UC Davis Health System. This eliminates them as options.

One concern of prescription diet pills is long-term safety. Sibutramine is an example of this. The FDA gave its approval for this weight loss drug in 1997, but then removed it from the market in 2010 when studies revealed it could increase the risk of nonfatal heart attack and stroke, explains MedlinePlus.com. People with high blood pressure are already at risk for these cardiovascular complications. Taking diet pills whose long-term effects are not immediately identifiable may increase the risks of these complications.

The obvious reason for taking diet pills is obesity, a common risk factor for high blood pressure. Ironically, the use of diet pills for weight reduction may also reduce high blood pressure. Orlistat is one diet pill that doesn't appear to have an adverse effect on your blood pressure, but your doctor should make the final decision. Patients must realize, however, that diet pills alone are not effective. You must incorporate a healthy eating and exercise plan for long-term success and improved health.

Many over-the-counter pills are available without a doctor's prescription, but they may be harmful to your health. Palo Alto Medical Foundation, or PAMF, refers to them as anorectic drugs, a medical term for diet pills. PAMF explains these pills are similar to amphetamines, although the effects are not as potent. Among the adverse side effects is an increase in blood pressure. Some pills to watch for include Tenuate, Adipex-P, Bontril and phentermine. Although some require a doctor's prescription, they are available illegally through online pharmacies.

The "Dietary Approach to Stop Hypertension," or DASH diet, is an eating plan designed specifically for people with high blood pressure. It lowers sodium intake, along with saturated fat and cholesterol. It focuses on whole grains, fruits and vegetables, helping lower blood pressure and improve your health. The National Heart Lung and Blood Institute states patients following the DASH diet not only lowered their blood pressure, but lost weight over an 18-month period.