Steroid-type replacement medications may cause side effects, particularly if the doses are high and are used long term.

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Antifungal drugs may cause side effects ranging from skin rashes to liver damage.

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Extended-release forms of these medications, including the skin patch or gel, may cause fewer side effects.

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Treatment with Belviq may cause serious side effects, including serotonin syndrome, particularly when taken with certain medicines that increase serotonin levels or activate serotonin receptors.

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It may cause potentially severe side effects, like depression, inflammatory bowel disease and birth defects.

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Moreover, he says, aspirin may have more side effects--it can cause ulcers or intestinal bleeding.

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The side effects from the medicine can also be nasty: Ivermectin may cause fever, itching, skin rash, joint or muscle pain, rapid heartbeat, and painful, tender glands.

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Meanwhile, scientists are continuously coming up with possible biomarker tests that may predict whether a given drug is likely to be effective, or is likely to just cause side effects.

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