Wow. The stuff you learn on the Internet.
Apparently Jeff Conaway, who played Zack on B5 was on a vh1 reality show called Celebrity Fit Club. He left the show midway through because apparently he had to go to drug rehab.
There's more details here:
http://en.wikipedia.org/wiki/Celebrity_Fit_Club#Season_three_-_2006but I've clipped some of the relevant bits below.
Quote:
In a flashback, Jeff showed up at Fit Camp on Day 15 in a bad condition. Dr. Ian Smith showed up to check on Jeff's condition in the hopes that he's well enough to compete. Jeff can't talk straight. Jeff can't walk straight. He can't even walk on his heels, which he blames on flat feet. Ian asks why Jeff's like this. Jeff blames it on the two Benadryl he took. Ian told Jeff he knows that two Benadryl alone do not produce Jeff's stupor. Back at the weigh-in, Jeff apologizes half-heartedly for taking two Benadryl and for being Jeff Conaway. Ian asks about Jeff's medications, recalling Jeff's supposed Benadryl
blitz. Jeff says he also takes muscle relaxers. He claims to have been clean and sober for fifteen of the last twenty years.
On another episode, Jeff melts down, saying "You can take your ****in' show and shove it up your ****in' ass." He later apologizes again, this time to Kelly. He once again blames the Benadryl for his loopiness. Chastity comes out and tells Jeff that the group thinks
he's on drugs. Jeff says he's only on prescriptions. Chas lets Jeff know that she was taking only prescriptions when she became addicted to them. She was in constant pain, too, but she came out of it, and encourages Jeff to do the same.
After his temper tantrum in the last episode, Dr. Linda Papadopoulis, scheduled a one-on-one with Jeff the following evening. However, he never showed up. Instead, he was rushed to the ER after a near-fatal night of painkillers and alcohol. After his release, Jeff explains that it was his birthday and he celebrated by taking too many benzoids
while he was drunk. He remembers waking up surrounded by paramedics. Later that day, he makes a visit to addiction specialist and Loveline co-host Dr. Drew Pinsky. Dr. Drew learns that Jeff is on one to three Norco, which is equivalent to six Vicodin, and six two-mg Xanax a day. As Dr. Drew says, he needs to stay in a hospital to detox from that
much Xanax.
/quote.
Spicy stuff, eh?