The narrator and star of the viral video "Kony 2012" was taken by police to a medical facility on Thursday morning after he was allegedly seen partially clothed and behaving irrationally in a San Diego neighbourhood.
Media reports indicate Jason Russell, 33, was also seen masturbating in public, but this was not confirmed by local police.
Mr. Russell is a co-founder of Invisible Children, a controversial charity that works in war-affected regions of Central Africa and released the video about warlord Joseph Kony last week.
Danica Russell said late Friday that her husband "did some irrational things brought on by extreme exhaustion and dehydration." She denied that alcohol or drug use triggered the behaviour.
"We thought a few thousand people would see the film, but in less than a week, millions of people around the world saw it. While that attention was great for raising awareness about Joseph Kony, it also brought a lot of attention to Jason and, because of how personal the film is, many of the attacks against it were also very personal, and Jason took them very hard," she said.
"On our end, the focus remains only on his health, and protecting our family. We'll take care of Jason, you take care of the work," her statement continued. "The message of the film remains the same: stop at nothing."
Police in San Diego said they responded to calls about a man acting in a "bizarre and irrational manner" in Pacific Beach around 11:30 a.m. on Thursday. The man was interfering with traffic, yelling incoherently and pounding his fists on the sidewalk, they said.
"Several callers reported the male was wearing only underwear and running into the street," a news release from the San Diego Police Department says. "One caller reported that the male had removed his underwear and was nude, perhaps masturbating, but that was not confirmed by responding officers."
Several people tried to calm him down, but were unsuccessful, police said.
A spokeswoman from the San Diego Police Department told NBC that he may have been under the influence of something. He was not arrested or charged with anything.
Police have not released the man's identity, but a statement from Invisible Children, posted on the organization's blog Friday afternoon, confirms that Mr. Russell was hospitalized after suffering from "exhaustion, dehydration, and malnutrition."
"The past two weeks have taken a severe emotional toll on all of us, Jason especially, and that toll manifested itself in an unfortunate incident yesterday," the statement, posted by Invisible Children CEO Ben Keesey says.
Mr. Keesey asked people to give Mr. Russell's family privacy while he deals with what he called a "personal health issue."
Invisible Children's 30-minute video has been viewed by millions of people since it was released last week. It calls on people to make Mr. Kony, who is wanted by the International Criminal Court for crimes against humanity, a "household name" to facilitate his arrest.
But many African writers and aid experts have criticized the video, saying it presents an overly simplistic, and sometimes inaccurate portrayal of problems in Central Africa. A screening of the film in Uganda was abruptly cancelled earlier this week after angry viewers threw stones, forcing the organizers to flee.
In an earlier public statement, the charity implored its critics to focus on stopping Mr. Kony, rather than critiquing the video.
"Let's focus on what matters, and what we DO agree on: Joseph Kony needs to be stopped," the statement says. "And when that happens, peace is the limit. This is the beautiful beginning of an ending that is just the beginning. We are defending tomorrow. And it's hopeful."
With reports from Associated Press and Oliver Moore