18 Pa.C.S. § 2714: Unauthorized administration of intoxicant.

A person commits a felony of the third degree when, with the intent to commit an offense under section 3121(a)(4) (relating to rape), 3123(a)(4) (relating to involuntary deviate sexual intercourse), 3125(5) (relating to aggravated indecent assault) or 3126(a)(5) (relating to indecent assault), he or she substantially impairs the complainant's power to appraise or control his or her conduct by administering, without the knowledge of the complainant, drugs or other intoxicants.