Certain medications, and some medical conditions such as viruses or a thyroid disorder, can cause the same symptoms as depression.

Synthetic hormones are used clinically to prevent pregnancy, control insulin levels in diabetics, compensate for a deficient thyroid gland and alleviate menopausal symptoms.

Protect yourself: Talk to a doctor about bothersome symptoms (especially if you're a woman — you're at higher risk for hypothyroidism).