Which dietary Supplements may be risky for COVID-19?
Dietary supplements for COVID-19 (role of vitamin C, zinc and vitamin D in treatment of COVID-19).
More than 4 in 10 people have increased their use of supplements since the start of the COVID-19 pandemic. Reinforce that there's still no evidence any supplement helps prevent or treat COVID-19. Not all supplements are risky. But clarify which products to avoid. Many patients swear by "immune boosters" such as colloidal silver, echinacea, green tea, selenium or vitamin C or D.
- Tell patients to AVOID colloidal silver due to risk of blue-gray skin discoloration, seizures, and liver or kidney toxicity. Explain that drinking green tea seems safe. But caution about cases of liver toxicity with oral green tea extract.
- If patients want to take vitamins or minerals, recommend usual daily doses, higher doses may do more harm than good.
- Some supplements are touted for antiviral effects, such as elderberry, garlic, oleander, quercetin or zinc.
- Warn that oleander is poisonous. It contains oleandrin, a cardiac glycoside similar to digoxin that may cause fatal arrhythmias. Be aware, there's not currently an oleander supplement but it's a common flowering shrub. Educate not to consume any part.
- Advise not to make elderberry syrup at home. The plant has a cyanide-producing chemical that can be toxic if not cooked properly.
- Watch for interactions with garlic, it may increase the risk of bleeding in patients taking an anticoagulant or antiplatelet.
- If patients try zinc, suggest an oral form. Nasal zinc products are floating around online but warn these may cause permanent loss of smell.
- Supplements are often promoted for stress, anxiety, or sleep, such as ashwagandha, chamomile, kava, passion flower, or valerian. Advise monitoring TSH if patients on a thyroid med start ashwagandha, it may stimulate thyroid hormone production. Caution about reports of liver toxicity with kava. Continue to ask about supplement use when updating medication lists.
NPS-adv
References
- Office of Dietary Supplements - Dietary Supplements in the Time of COVID-19.
- Oketch-Rabah HA, Roe AL, Rider CV, et al. United States Pharmacopeia (USP) comprehensive review of the hepatotoxicity of green tea extracts. Toxicol Rep. 2020;7:386-402.
