What causes an increased sex drive?

Answer:
The exact causes of increased sex drive (or 'libido') are still somewhat unknown. However, many scientists believe it is caused by hormone imbalances or by conditions that cause severe mood swings. There are no known drugs that safely increase libido for either gender.
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Contributor: Bleepy
First answer by Bleepy. Last edit by Spermbrain. Contributor trust: 38 [recommend contributor recommended]. Question popularity: 82 [recommend question].