WASHINGTON (AP) _ Bristol-Myers Co. says its new anti-anxiety drug can provide relief without causing drowsiness or other side effects of commonly used tranquilizers that impair a person's ability to function normally.

BuSpar, which will be available by prescription beginning in early December, is ''a totally new chemical compound'' unlike the current class of tranquilizers, company spokesman Scott Litherland said Wednesday.

Unlike Valium and other benzodiazepines, BuSpar is believed to act directly on brain receptors responsible for anxiety and does not depress the entire central nervous system, Litherland said.

The Food and Drug Administration approved the drug, buspirone hydrochloride, which will be marketed by Bristol-Myers' Mead Johnson Pharmaceutical Division.

''To many of those who suffer from anxiety, this new drug may offer an effective and less restrictive form of treatment,'' FDA Commissioner Frank E. Young said in a statement Wednesday.

FDA spokesman Brad Stone said that while the drug can cause upset stomach, diarrhea, dizziness and headaches, the side effects are less severe than the sedation associated with Valium and other benzodiazepines.

''It won't affect your ability to perform everyday tasks like driving or operating heavy machinery,'' Stone said. ''It's a new class (of drug) that offers some advantages in terms of allowing people to function normally.''

Bristol-Myers developed the drug in 1967 and has conducted clinical trials with humans since 1978, Litherland said.

The trials found no evidence that buspirone hydrochloride causes physical dependency, Stone said.

Bristol-Myers said the drug ''may offer an additional margin of safety for patients'' because in combination with alcohol it appears to cause none of the adverse reactions that can occur with the other tranquilizers.

Additionally, ''BuSpar dues not cause the euphoric or sedative effects which can often lead to abuse ... (and) is unlikely to be utilized by illicit drug users,'' the company said.

Stone noted that, unlike Valium and other similar drugs, BuSpar is not useful as a muscle relaxant or anti-convulsive agent. He also said the drug initially is not as effective in patients previously treated with benzodiazepines.

The American Psychiatric Association estimates that more than 13 million Americans suffer from general anxiety disorders, which are characterized by persistent physical tension, hyperactivity in certain bodily functions, pervasive feelings of apprehension and emotional agitation, Stone said.