Ed Buck, a Democratic donor and activist whose West Hollywood apartment was the scene of two methamphetamine overdose deaths since 2017, was arrested on Tuesday after investigators said a third man suffered an overdose in his home last week.

Mr. Buck, 65, who has not faced charges for the earlier overdoses but was subject to a wrongful-death lawsuit, was charged on Tuesday with battery causing serious injury, administering methamphetamine and maintaining a drug house. He faces up to five years and eight months in prison.

The charges relate only to the most recent incident, on Sept. 11, when the Los Angeles district attorney’s office says Mr. Buck injected a 37-year-old man with methamphetamine in Mr. Buck’s home. The man, who was not identified, survived the overdose.

Families of the two men who died in his apartment — Timothy Dean, 55, died in January, while Gemmel Moore, 26, died in July 2017 — have accused Mr. Buck, who is white, of preying upon black gay men.