Sara has trouble sleeping, so her doctor gave her medicine that contains melatonin. Sara most likely has a problem with which gland?

The pineal gland produces melatonin, a hormone that helps regulate the sleep-wake cycle. Since Sara’s medicine contains melatonin to help with sleep, the gland most closely associated with her problem is the pineal gland. The adrenal, thymus, and pituitary glands do not primarily produce melatonin.

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