Antidepressants may cause mild side effects that usually do not last long. Any unusual reactions or side effects should be reported to a doctor immediately.
The most common side effects associated with SSRIs and SNRIs include:

• Headache, which usually goes away within a few days.
• Nausea (feeling sick to your stomach), which usually goes away within a few days.
• Sleeplessness or drowsiness, which may happen during the first few weeks but then goes away. Sometimes the medication dose needs to be reduced or the time of day it is taken needs to be adjusted to help lessen these side effects.
• Agitation (feeling jittery).
• Sexual problems, which can affect both men and women and may include reduced sex drive, and problems having and enjoying sex.

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