About triamterene
Triamterene is a potassium-sparing diuretic (in other words, it inhibits the urinary excretion of potassium). Diuretics increase urinary water loss from the body and are used to treat high blood pressure, congestive heart failure, and some kidney or liver conditions. Triamterene is available as a single agent and in combination products.
Helpful Products
Try these helpful products which may be beneficial if taken with this medicine
- Calcium with vitamin D
- To avoid bone loss, try taking 1,000 mg of calcium and 400 IU of vitamin D daily
- Salty foods
- Restricting dietary salt while taking triamterene might result in excessive sodium loss, so talk to your healthcare provider before drastically reducing salt intake
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Continue reading the full article for more information on interactions with vitamins, herbs, and foods.
Summary of Interactions with Vitamins, Herbs, and Foods
In some cases, an herb or supplement may appear in more than one category, which may seem contradictory. For clarification, read the full article for details about the summarized interactions.
 May be Beneficial: Depletion or interference—The medication may deplete or interfere with the absorption or function of the nutrient. Taking these nutrients may help replenish them. | Calcium* Folic acid* |
| May be Beneficial: Side effect reduction/prevention—Taking these supplements may help reduce the likelihood and/or severity of a potential side effect caused by the medication. | Folic acid |
 Avoid: Adverse interaction—Avoid these supplements when taking this medication because taking them together may cause undesirable or dangerous results. | Buchu Cleavers Dandelion Gravel root Horsetail Juniper Magnesium Uva ursi |
 Check: Other—Before taking any of these supplements or eating any of these foods with your medication, read this article in full for details. | Potassium Sodium |
| Supportive interaction | None known |
| Reduced drug absorption/bioavailability | None known |
An asterisk (*) next to an item in the summary indicates that the interaction is supported only by weak, fragmentary, and/or contradictory scientific evidence.
Interactions with Dietary Supplements
Calcium
A review of the research literature indicates that triamterene may increase calcium loss.1 The importance of this information is unclear.
Folic acid
Triamterene is a weak folic acid antagonist that has been associated with folic acid-deficiency anemia in people already at risk for folic acid deficiency.2 However, people treated long term with triamterene, without additional risk for folic acid deficiency, were found to have normal folic acid levels and no signs of folic acid deficiency.3 The use of multivitamin supplements containing folic acid appears to diminish the occurrence of birth defects associated with triamterene. According to one study,4 pregnant women who took folic acid–containing multivitamin supplements in addition to their prescription drugs had fewer babies with heart defects and deformities of the upper lip and mouth.
One study showed that people taking diuretics for more than six months had dramatically lower blood levels of folic acid and higher levels of homocysteine compared with individuals not taking diuretics.5 Homocysteine, a toxic amino acid byproduct, has been associated with atherosclerosis. Until further information is available, people taking diuretics for longer than six months should probably supplement with folic acid.
Magnesium
Preliminary research in animals suggests that triamterene may inhibit the urinary excretion of magnesium.6 It is unknown if this same effect would occur in humans. Persons taking more than 300 mg of magnesium per day and triamterene should consult with a doctor as this combination may lead to potentially dangerous increases in the level of magnesium in the body. The combination of triamterene and hydrochlorothiazide would likely eliminate this problem, as hydrochlorothiazide may deplete magnesium.
Potassium
As a potassium-sparing drug, triamterene reduces urinary loss of potassium, which can lead to elevated potassium levels.7 People taking triamterene should avoid potassium supplements, potassium-containing salt substitutes (Morton Salt Substitute, No Salt, Lite Salt, and others) and even high-potassium foods (primarily fruit). Doctors should monitor potassium blood levels in patients taking triamterene to prevent problems associated with elevated potassium levels.
However, some medications (for example, Dyazide, Maxzide) contain the combination of the potassium-sparing drug triamterene and the potassium-depleting drug hydrochlorothiazide. With the use of these combination medications, potassium excess and potassium depletion are both possible. People taking these drugs should have their potassium levels monitored by a doctor to determine whether their potassium intake should be increased, reduced, or kept the same.
Sodium
Diuretics, including triamterene, cause increased loss of sodium in the urine. By removing sodium from the body, diuretics also cause water to leave the body. This reduction of body water is the purpose of taking diuretics. Therefore, there is usually no reason to replace lost sodium, although strict limitation of salt intake in combination with the actions of diuretics can sometimes cause excessive sodium depletion. On the other hand, people who restrict sodium intake and in the process reduce blood pressure may need to have their dose of diuretics lowered. People taking triamterene should talk with their prescribing doctor before severely restricting salt.
Interactions with Herbs
Diuretic herbs
Herbs that have a diuretic effect should be avoided when taking diuretic medications, as they may enhance the effect of these drugs and lead to possible cardiovascular side effects. These herbs include dandelion, uva ursi, juniper, buchu, cleavers, horsetail, and gravel root.8
Interactions with Foods and Other Compounds
Food
Triamterene is best taken after meals to avoid stomach upset.9
References
1. Werbach WR. Foundations of Nutritional Medicine. Tarzana, CA: Third Line Press, 1997, 246 [review].
2. Jackson EK. Diuretics. In Goodman & Gilman’s The Pharmacological Basis of Therapeutics, 9th ed. New York: McGraw Hill, 1996, 706.
3. Mason JB, Zimmerman J, Otradovec CL, et al. Chronic diuretic therapy with moderate doses of triamterene is not associated with folate deficiency. J Lab Clin Med 1991;117:365–9.
4. Hernández-Díaz S, Werler MM, Walker AM, Mitchell AA. Folic acid antagonists during pregnancy and the risk of birth defects. N Engl J Med 2000;343:1608–14.
5. Morrow LE, Grimsley EW. Long-term diuretic therapy in hypertensive patients: effects on serum homocysteine, vitamin B6, vitamin B12, and red blood cell folate concentrations. South Med J 1999;92:866–70.
6. Devane J, Ryan MP. The effects of amiloride and triamterene on urinary magnesium excretion in conscious saline-loaded rats. Br J Pharmacol 1981;72:285–9.
7. Jackson PR, Ramsay LE, Wakefield V. Relative potency of spironolactone, triamterene and potassium chloride in thiazide-induced hypokalaemia. Br J Clin Pharmacol 1982;14:257–63.
8. Brinker F. Herb Contraindications and Drug Interactions. Sandy, OR: Eclectic Institute, 1997, 102–3.
9. Threlkeld DS, ed. Diuretics and Cardiovasculars, Potassium-Sparing Diuretics, Triamterene. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Jul 1993, 138k–9.
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2006-09-07
