Before you take these...

Aspirin warning: Women who need relief from menstrual cramps should be aware that aspirin or aspirin-based pain relievers intensify the risk for vocal fold hemorrhage. Blood vessels in the vocal folds - already swollen due to hormonal changes - become even more vulnerable if aspirin is used and can burst from vigorous or overly enthusiastic speaking or singing.

Birth control pills: Some combination pills may cause a temporary lowering of the voice, making it somewhat difficult to sing in the upper part of the voice. Teachers who are singers should be aware of this. Most changes due to the pill are reversible. However some pills formulated outside the U.S. are less regulated and could contain androgenic agents that can permanently lower the voice.