Potassium-saving diuretics

Active substances and pharmaceuticals concernedSpecially affected active substances and pharmaceuticalsMechanism of interactionConsequences and possible symptoms of the interactionRecommended SupplementationSpecial instructions for useReferences

Active substances and pharmaceuticals concerned

Name of active substance	Trade name	Affected micronutrients
Spironolactone	Spirobene®, Spirohexal®	Potassium Zinc
Amiloride	Amilostad®, Moduretic®
Triamterene	Dytide H®

Specially affected active substances and pharmaceuticals

Drug name	Trade name	Affected micronutrients
Triamterene	Dytide H®	Folic acid

Mechanism of interaction

Mechanism of interaction
Potassium	Spironolactone as an aldosterone antagonist blocks the penetration of aldosterone into the cell nucleus. Therefore, aldosterone-induced protein formation does not take place at sufficient rates and as a result sodium absorption is reduced and potassium excretion is reduced. WARNING: uncontrolled self-medication with potassium leads to an increase in potassium levels.
Folic acid	The absorption and bioavailability of folic acid is reduced by the folic acid antagonistic effect of triamterene.
Zinc	The amount of zinc excreted by the urine is increased by potassium-sparing diuretics.

Consequences and possible symptoms of the interaction

Consequences of the interaction		Possible symptoms
Potassium	Increase in potassium levels	Hyperkalemia Neuromuscular disorders Cardiovascular disorders
Folic acid	Decrease in folic acid levels	Anorexia, pallor, depression, weakness, forgetfulness Risk of neural tube defects during pregnancy Impairment of erythropoiesis and development of pernicious anemia, thrombocytopenia, leukopenia, hyperhomocysteinemia Increased risk of stroke due to increase in blood homocysteine levels Increased risk of dementia and polyneuropathy Glossitis, stomatitis, mucosal atrophy in the GIT and urogenital tract
Zinc	Decrease in zinc levels	Wound healing disorders, hair loss, brittle, white spotted nails Increased susceptibility to infections Concentration disorders, hyperactivity, depression

Recommended Supplementation

Medical substance	Recommended supplementation	Dosage
Triamterene	Folic acid	0.4-1 mg/d p.o.
All	Zinc	20 mg/d p.o.

Special instructions for use

Instructions for use
Spironolactone	Do not self-medicate with potassium. If ACE inhibitors and AT1 antagonists are taken simultaneously, the risk of hyperkalemia increases significantly.
Folic acid	A combination with a B complex is recommended.

References

Ben Salem C et al. Drug-induced hyperkalemia. Drug Saf. 2014 Sep;37(9):677-92. doi: 10.1007/s40264-014-0196-1.
Gröber Uwe: Mikronährstoffe. Metabolic Tuning – Prävention – Therapie. 3. Auflage, 2011
Gröber Uwe: Arzneimittel und Mikronährstoffe. Medikationsorientierte Supplementierung. 3. akt. und erw. Auflage, 2014
Stargrove Mitchell Bebel, Treasure Jonathan, McKee Dwight L.: Herb, Nutrient, and Drug Interactions: Clinical Implications and Therapeutic Strategies. 2008
Tubek S. Differences in selected zinc metabolism parameters in obese and normal-weight hypertensive patients following treatment with spironolactone. Biol Trace Elem Res. 2006 Winter;114(1-3):135-41.
Zimmerman J, Selhub J, Rosenberg IH. Competitive inhibition of folic acid absorption in rat jejunum by triamterene. J Lab Clin Med. 1986 Oct;108(4):272-6.