The fruit of Schisandra chinensis, also spelled schizandra, is an herbal remedy people use for preventing and treating liver problems, improving heart function, relieving coughing and wheezing and improving exercise performance. The Memorial Sloan-Kettering Cancer Center notes that animal research indicates schizandra has a protective effect on the liver, but research is needed to confirm any benefits in humans. Reported side effects are minor.
Restlessness and Insomnia
An article published in the October 1998 issue of "Alternative Medicine Review" notes the low toxicity of schizandra. The author remarked on restlessness and insomnia as possible overdose effects when taking more than the standard dose. The typical dosage is 450 mg powdered herb in capsules three times daily, or 2 ml tincture in 1 part schizandra to 3 parts base three times daily.
The "Alternative Medicine Review" article also listed breathing problems, or dyspnea, as a possible overdose side effect of schizandra. The Memorial Sloan-Kettering Cancer Center notes that schizandra berry has central nervous system depression properties, which can account for this side effect.
Gastrointestinal Side Effects
Gastrointestinal side effects also are possible when taking schizandra berry, as noted by the University of Michigan Health Center. A person taking schizandra supplements may experience lack of appetite, heartburn and stomach upset.
As with any herbal remedy, in rare cases someone may experience an allergic reaction to schizandra berry. Signs listed by the Physicians' Desk Reference include difficulty breathing, tightness in the chest or throat, chest pain, itchy or swollen skin and a skin rash or hives. An allergic reaction to schizandra berry should be considered a medical emergency.