droguer

To drug someone, often covertly (spiking a drink) or, reflexively, se droguer — to take drugs habitually; the non-reflexive form usually implies something done to someone else, often with sinister intent.

• Quelqu'un a drogué sa boisson à son insu. — Someone drugged his drink without his knowledge.
• Il se drogue depuis qu'il est adolescent. — He's used drugs since he was a teenager.
• Le vétérinaire a dû droguer l'animal pour l'examiner. — The vet had to sedate the animal to examine it.

Non-reflexive droguer quelqu'un (to drug someone else, often covertly) and reflexive se droguer (to use drugs oneself) carry quite different connotations — mixing them up can accidentally imply someone was a victim rather than a user, or vice versa.