SAN FRANCISCO (San Francisco Chronicle) — Amid growing reports of deaths and emergency-room visits from use of the popular "club drug" GHB comes even more disturbing news: Quitting GHB cold turkey may be lethal.

GHB is an easily made industrial solvent that is imbibed and gives users a euphoric high. While it was made illegal last year after several people died of GHB overdoses, it has become popular at night clubs, particularly among young people.

"If you look on the Internet on GHB, everyone says it's not addicting, it's safe, it doesn't cause dependence like heroin," said Jo Ellen Dyer of the California Poison Control Center based at San Francisco General Hospital.

But what she and her colleagues are finding is just the opposite. Withdrawal symptoms include shakiness, confusion, insomnia, delusions and even seizures. Dyer describes eight cases - including one Florida death - in Tuesday's issue of the Annals of Emergency Medicine.

GHB apparently retrains the pathways in the brain so that they are used to lower-than-normal levels of certain neurotransmitters. When GHB use is stopped, the brain is overwhelmed when more normal amounts of neurotransmitters return.

"If I didn't have it, I'd start freaking out - anxiety attacks, shaking uncontrollably. I went six months without sleeping," said Tony Southard, a North Carolina man who got hooked on GHB from a bodybuilder friend. After two years of using it almost around the clock, Southard said he needed a seven-day stay in the hospital under heavy sedation to wean his body off the drug.

"It's the hardest thing I ever did," he said. In Florida, a 24-year-old man who had been using GHB for more than 10 months was admitted to the hospital after suffering from severe delirium. He died 13 days later of a fatal heart rhythm disturbance, Dyer said.

The other seven withdrawal cases Dyer described were all from the Bay Area, where GHB has become a popular club drug.

In each case, the patients had severe delirium with hallucinations, required heavy sedation and had to be admitted to the intensive care unit, Dyer said. Their hospital stays ranged from five to 15 days.

After being discharged, some patients experienced continued drug cravings and depression, although at this point no other long-term consequences from GHB dependence are known.

Gamma-hydroxybutyrate was first used in the bodybuilder community because of its purported effects on muscle growth. It soon became a popular club drug because of the euphoric high, which wears off fairly quickly.

Originally marketed as a "natural" and "nontoxic" dietary supplement, GHB has been linked to several overdose deaths. Its toxic effects include vomiting, depressed breathing, loss of consciousness and seizures.

In response to the rising use of the drug and many fatal overdoses, as well being used as a date-rape drug, the federal government made GHB illegal last year. Cousins of GHB, which have the same effect on the body, are also illegal, but are being sold on the Internet.

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