Herbal Remedies and Supplements that are Potentially Unsafe

The year 2020 has the whole world reaching for alternative ideas to keep them in the best of health. Immune boosters include supplements such as echinacea, colloidal silver, green tea, selenium, vitamin C, and vitamin D. Antiviral supplements include elderberry, garlic, oleander, quercetin, and zinc. While most supplements are safe in all situations, some supplements have potential risks attached to them.

The following are potentially unsafe plants or supplements for some patients.

Oleander has led to fatal poisonings. All parts of the plant contain cardiac glycosides which can cause problems in the heart.

Colloidal silver accumulates in the body and can cause permanent skin discolouration, neurologic toxicity (e.g., seizures), and liver or kidney damage.

Intranasal zinc can cause permanent loss of smell.

Ashwagandha (an “adaptogen”) should be avoided in pregnancy, as it may cause miscarriage. It is safe for nonpregnant adults at doses up to 1,000 mg/day for up to 12 weeks. It may rarely cause stomach side effects and rashes, and extremely rarely, liver toxicity. It may rarely stimulate thyroid hormone production or secretion.

Green tea (beverage) should be limited to eight cups daily, due to caffeine content. Green tea oral extract is safe when used as directed, however, there are rare reports of liver toxicity with green tea extracts. Take this form with food to limit this risk. It should be avoided in patients with liver impairment.

Elderberry extract is safe. But people allergic to grass pollen might experience runny noses or indigestion. Homemade remedies using the raw or unripe fruit, or plant parts other than the fruit, should not be consumed; they contain cyanogenic glycosides that can cause stomach side effects. Proper cooking eliminates the toxin, but teas and hot drinks have also caused stomach problems. Neurologic side effects have also been reported.

Quercetin is generally well-tolerated but rarely can cause headache and a burning, prickling sensation in the hands, arm, feet and legs.

The following supplements are safe when taken by mouth:

Echinacea, garlic (allow watch for blood-thinning effects), and American ginseng.

Panax ginseng (red ginseng) is safe when used for up to six months. Hormonal effects are of concern with longer use.

Resveratrol is safe when consumed in foods, but high doses of supplements may cause stomach side effects.