According to Dr. Gallimberti , the action of GHB is “without serious side effects.” Some research programs have reported no side effects at all. Nonetheless, it’s clear that some minor side effects can occur. Those most commonly experienced are drowsiness, dizziness, nausea, and sometimes vomiting. As a sedative-hypnotic, GHB’s effects bear some similarity to those of alcohol and tranquilizers. GHB not only “may cause drowsiness” like these other drugs, IT WILL ALMOST INVARIABLY DO SO. Ataxia, or incoordination, can also be a side effect of GHB. DO NOT DRIVE A VEHICLE OR OPERATE DANGEROUS MACHINERY WHILE UNDER THE INFLUENCE OF GHB. As mentioned, clonic movements (muscle contractions or “seizures”) have been observed during the onset of GHB-induced sleep. Headache is sometimes reported. A moderate slowing of the heart rate is a consistent effect, and small changes in blood pressure can take place. Likewise, orthostatic hypotension (a sudden drop in blood pressure caused by standing up quickly) has also been reported. Sometimes this is experienced as brief dizziness, and rarely people can briefly lose consciousness. At very high doses, cardiac and respiratory depression can occur. Sufficiently large doses of GHB can cause sudden sedation and loss of consciousness. Do not take such doses except when reclining on a bed or sofa. It is also a bad idea to take such doses in the presence of people who don’t know anything about GHB. You may alarm your family or friends and wake up in an emergency room (with a large medical bill). More unusual and extreme reactions have included diarrhea, lack of bladder control, temporary amnesia, and sleepwalking. Whatever side effects may be noted, they are often much more severe when GHB is combined with other central nervous system depressants [Chin and Kreutzer, 1992, Gallimberti, 1989; Takahara, 1977; Vickers, 1969].