The American Bar Association yesterday overwhelmingly approved a sweeping program to combat teen-age alcohol and drug abuse, including efforts to raise the drinking age to 21 nationwide.

But the 300,000-member lawyers' organization, completing a week-long convention here, backed away from endorsing a tax increase on alcohol to pay for the prevention, treatment and research programs it approved.

Supporters of the 20-point program called its passage "very significant," saying it would spur action to combat teen-age alcohol and drug abuse, especially efforts to raise the drinking age to 21 in 13 states and the District where the minimum age is still 18.

The package, passed by voice vote, calls on the Defense Department, which has resisted age restrictions on military bases, to adopt 21 years as the minimum age.

It also calls on states to increase criminal penalties for selling alcohol or drugs to minors, to establish or expand treatment programs and to permit lawsuits against those who serve alcohol to minors who are later involved in accidents.

Florida bar delegate Martha Barnett called the program a "comprehensive national strategy . . . to provide treatment, education and law reform and to finance research and treatment programs."

Other supporters said lobbying efforts by the brewery industry forced the ABA to cave in on tax increases that would have provided funding for treatment.

David Evans, a New Jersey delegate who helped draft the program, denied yielding to brewery pressure, but said the industry mounted a strong attack.

William W. Falsgraf, the new ABA president, denied the lobbying effort influenced the ABA's action. "It had nothing to do with the brewer's lobby," he said. "They didn't lobby me."

Falsgraf, who is from Cleveland, said the tax idea was dropped when state and local government tax experts said collecting such a specific-purpose tax would cause an administrative nightmare and consume most of the revenue generated.

Falsgraf, in a news conference, said he would pursue several goals during his one-year tenure, including efforts to focus attention on international terrorism, to help developing countries increase the power of independent judiciaries and to increase participation by women and minorities in the ABA.

There is a "perception that the ABA is run by white males, middle-aged or over," Falsgraf said, but "we are the only game in town and, for better or worse, we are the voice of lawyers." He called on women and minorities to join the organization.

Falsgraf said he was not present Tuesday when the ABA narrowly defeated a proposal to ban discrimination against homosexuals, but said he would have voted with the losing side. The issue "will come up again," he predicted.