Need to Know: Cautions, Side-effects and Interactions

Cordyceps is deemed a very safe herb, with no known contraindications or toxicity (Holliday & Cleaver 2008). Studies in a variety of animal models have shown that a lethal dose could not be detected, nor has any type of mutagenic or harmful effects on bodily functions been discovered (Cleaver et al., 2005). Few side effects have been reported and are limited to nausea and stomach uneasiness, accompanied in some cases by dry mouth (Zhou et al., 1998). Only a single report of a systemic allergic reaction to cordyceps exists (Zhou et al., 1998).

Cordyceps is frequently used in medicinal mushroom mixtures working synergistically to fight cancer, reduce inflammation and alleviate toxicity in anti-retroviral therapy (Holliday & Cleaver, 2008; Smith, Rowen & Sullivan, 2005; Wang et al., 2001). Drug interactions are few, especially with antiretroviral and insulin medication among others, leading to a lesser amount of the drug to be used (Holliday & Cleaver 2008). 

Cordyceps and other medicinal mushrooms described by
Dr. Georges Halpern in his book "Healing Mushrooms".

Due to the known effect of cordyceps to enhance glucose metabolism and insulin sensitivity, it is known to decrease the amount of insulin injections required by diabetic patients (Guo, Han & Lio, 2010; Zhu et al. 1998). In vitro studies have shown inhibition of human platelet aggregation, which suggests that high doses of cordyceps may potentiate anticoagulants (Cho et al., 2007). The adenosine component of cordyceps is also marketed as an anti-HIV drug. Anti-retroviral drugs are toxic, thus caution should be taken when using these therapies in conjunction with high doses of cordyceps (Holliday & Cleaver, 2008).

Currently, more potent types of Cordyceps are being cultivated, thus there is always potential for drug interactions especially when high doses are consumed (Cleaver et al., 2005).