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n. an herbal agent derived from any of nine related plant species native to the United States and southern Canada, with Echinacea purpurea being the most commonly used and perhaps the most potent. Echinacea traditionally has been used in the belief that it stimulates the immune system and prevents or treats colds. Some studies have shown, however, that taking echinacea has no significant effects on preventing colds or reducing their severity or duration. Although it is generally considered safe and there are no known reports of toxicity, some people may experience hypersensitivity reactions to echinacea, such as rashes, increased asthma, and anaphylaxis. More common side effects include headache, dizziness, nausea, and constipation. People with autoimmune disorders (see autoimmunity), leukemia, multiple sclerosis, tuberculosis, and HIV infection should not take echinacea. Concurrent use with immunosuppressant agents should be avoided, and, as echinacea is believed to be metabolized by the cytochrome P450 3A4 enzyme, it accordingly has numerous potential interactions with psychotropic drugs metabolized via the same enzyme (e.g., clonidine, nefazodone, St. John’s wort).

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Psychology term of the day

February 26th 2024

confirmatory research

confirmatory research

research conducted with the aim of testing one or more preexisting hypotheses. Compare exploratory research.