Just because they're "natural" doesn't mean herbal supplements don't have side effects. You still need to do your homework, or, better still, consult with an expert before using a natural remedy. Know the potential side effects and how the supplement might interact with any drugs or other supplements you are taking. Certain supplements can raise your blood pressure or interfere with blood pressure-lowering drugs. Some you may need to avoid.
Licorice Root
Licorice root or its extract is an effective treatment for stomach ulcers, sore throats, congestion and, because it is an adaptogen--meaning it helps resist stress--is often included in small amounts in Chinese herbal formulas. In small amounts, licorice is safe, says David Winston, a registered herbalist with the American Herbalists Guild. But in larger amounts, a component of licorice, glycyrrhizic acid can increase blood pressure. It affects the kidneys' ability to remove fluid from the bloodstream. The result is a potentially serious syndrome with hormone and electrolyte imbalances, including low potassium levels and high blood pressure. This condition has been linked to too much real licorice candy, licorice-flavored chewing tobacco and straight licorice tea. You should avoid using licorice if you have high blood pressure, especially if you are taking a potassium-depleting diuretic, such as thiazides or loop diuretics, Winston says. You can avoid the blood-pressure elevating effects of licorice by using deglycyrrhized licorice.
Yohimbe
With stimulant and aphrodisiac properties, yohimbe is used most often for impotence and for general sexual dysfunction in men and women. It has the potential to cause high blood pressure, especially when it is used along with large amounts of certain foods: those containing tyramine, which includes aged cheeses, fermented meats and red wines, and those containing vasopressors: overripe fava beans, coffee, tea, colas and chocolate. "I would avoid using it altogether unless you have a prescription for yohimbe hydrochloride and are under medical supervision," Winston advises.
Bitter Orange Extract
Found in some weight loss products, bitter orange extract is a concentrated source of synephrine, a substitute for ephedra, a compound banned in the U.S. after its use was linked to a number of deaths. "Synephrine doesn't seem to have the same central nervous system stimulating effects as ephedra, but I wouldn't consider it a natural product, and I am not a big fan of it," Winston says. "It's questionable whether it works. I would not recommend its use, for anyone." On the other hand, bitter orange itself (not the concentrated extract) is found in Seville oranges, used for marmalade, and in a number of food products. It does not contain enough synephrine to raise blood pressure, WInston says.
Guarana
The beans of this South American plant contain twice as much caffeine as coffee beans. Guarana is used for weight loss, to enhance athletic performance and to reduce mental and physical fatigue. It's often used in energy drinks or pills. Caffeine stimulates the central nervous system, heart, muscles, and possibly the pressor centers that control blood pressure.
Caffeine can cause a short, but dramatic increase in your blood pressure, even if you don't have high blood pressure, according to researchers at the Mayo Clinic. They found that the amount of caffeine in 2 to 3 cups of coffee can raise your blood pressure by up to 10 points.
To see if caffeine might be raising your blood pressure, check your blood pressure within 30 minutes of drinking a cup of coffee or another caffeinated beverage you regularly consume. If it increases by five to 10 points, you may be sensitive to the blood pressure-raising effects of caffeine. In that case, it's best to avoid it altogether, but especially right before activities that naturally increase your blood pressure, such as exercise, weightlifting or hard physical labor.
Ginseng
Red Asian ginseng, found in small amounts in some energy drinks, can occasionally increase blood pressure in someone who is a "Type A," Winston says. "The combination of Red Asian ginseng, caffeine and sugar is particularly stimulating," he says. If you're drinking enough to make you jittery and your heart rate goes up, you're pretty much assured that your blood pressure is higher, too, Winston says. "It's best to back off."
St. John's Wort
This depression-relieving herb has been associated, in isolated cases, with a condition called serotonin syndrome. Symptoms include extreme anxiety, confusion, nausea, high blood pressure and fast heart rate. These symptoms may occur within two to three weeks after the herb is started. It is most likely to occur in people who are also taking a SSRI antidepressant. "It is very important not to combine antidepressant drugs and St. John's Wort, because the combination can cause problems," Winston says.
References
- The Natural Medicines Comprehensive Database: Search Natural Medicines
- The Mayo Clinic: How Does Caffeine Increase Blood Pressure
- David Winston, Registered Herbalist
