Loop diuretics (drug interactions)

  • DEFINITION: Used to reduce fluid accumulation in the body.
  • INTERACTIONS: Dong quai, licorice, magnesium, potassium, St. John’s wort, parsley, dandelion, vitamin B1
  • DRUGS IN THIS FAMILY: Bumetanide (Bumex), ethacrynic acid (Edecrin), furosemide (Lasix), torsemide (Demadex)

Potassium

Effect: Probable Need for Supplementation

Loop diuretics cause a constant and significant loss of potassium. The classic treatment for this is to eat bananas and drink orange juice. Potassium supplements are also frequently prescribed. However, potassium levels must be monitored, as high levels of potassium can also be dangerous.

Magnesium

Effect: Probable Need for Supplementation

Long-term use (more than six months) of loop diuretics might lead to magnesium deficiency. In turn, magnesium depletion can increase the loss of potassium.

Since magnesium deficiency is common anyway, taking a magnesium supplement at the standard US Dietary Reference Intake (formerly known as the Recommended Dietary Allowance) levels might make sense.

Vitamin B1

Effect: Probable Need for Supplementation

Evidence suggests that loop diuretics interfere with the body’s metabolism of vitamin B1 (thiamin). This effect may cause adverse consequences in one group of persons who commonly take loop diuretics: people with heart failure. The heart depends on B1 for proper function; therefore, this finding suggests that taking a B1 supplement may be advisable. Preliminary evidence suggests that thiamin supplementation improves heart function in persons with congestive heart failure (CHF).

Licorice

Effect: Possible Dangerous Interaction

Licorice also affects potassium, and the combination of licorice and loop diuretics might cause unexpected, rapid potassium loss. However, the special form of licorice known as DGL (deglycyrrhizinated licorice) should not affect potassium levels.

Dong Quai, St. John’s Wort

Effect: Possible Harmful Interaction

Loop diuretics have been reported to increase sensitivity to the sun, amplifying the risk of sunburn or skin rash. Because St. John’s wort and dong quai may also cause this problem, taking these herbal supplements during treatment with loop diuretics might add to this risk. It may be a good idea to wear sunscreen or protective clothing during sun exposure if one takes one of these herbs while using a loop diuretic.

Other Interactions

Loop diuretics cause fluid loss, and supplementation with herbs and supplements, such as dandelion and parsley, that also have this effect should be avoided. Further, several prescription medications should be avoided or taken with caution in combination with loop diuretics. The potassium loss caused by loop diuretics can increase the risk of digoxin toxicity. Loop diuretics can also increase lithium levels when taken with the drug. Nonsteroidal anti-inflammatory drugs can reduce the effectiveness of loop diuretics. Specific antibiotics, antihypertensive medications, corticosteroids, and antidiabetic medications should all be taken with caution and under the advice of a healthcare professional when an individual is also taking loop diuretics.

Bibliography

Brady, J. A., C. L. Rock, and M. R. Horneffer. "Thiamin Status, Diuretic Medications, and the Management of Congestive Heart Failure." Journal of the American Dietetic Association, vol. 95, 1995, pp. 541-544.

"Diuretics: Types, Uses and Side Effects." Cleveland Clinic, 1 Oct. 2021, my.clevelandclinic.org/health/treatments/21826-diuretics. Accessed 1 Oct. 2024.

Hardig, L., et al. "Reduced Thiamine Phosphate, but Not Thiamine Diphosphate, in Erythrocytes in Elderly Patients with Congestive Heart Failure Treated with Furosemide." Journal of Internal Medicine, vol. 247, 2000, pp. 597-600.

Huxel, Chris. "Loop Diuretics - StatPearls." NCBI, 22 May 2023, www.ncbi.nlm.nih.gov/books/NBK546656. Accessed 1 Oct. 2024.

Sole, M. J., and K. N. Jeejeebhoy. "Conditioned Nutritional Requirements: Therapeutic Relevance to Heart Failure." Deutsches Herzzentrum München, vol. 27, 2002, pp. 174-178.

Wichmann, Sine, et al. "Loop Diuretics in Adult Intensive Care Patients with Fluid Overload: A Systematic Review of Randomised Clinical Trials with Meta-Analysis and Trial Sequential Analysis." Annals of Intensive Care, vol. 12, no. 52, 13 June 2022, doi.org/10.1186/s13613-022-01024-6. Accessed 19 Dec. 2022.

Yue, Q. Y., et al. "No Difference in Blood Thiamine Diphosphate Levels Between Swedish Caucasian Patients with Congestive Heart Failure Treated with Furosemide and Patients Without Heart Failure." Journal of Internal Medicine, vol. 242, 1997, pp. 491-495.