A House subcommittee yesterday criticized the Food and Drug Administration for allowing increasing numbers of new prescription drugs to be sold without government approval of their safety and effectiveness.

Noting that at least 5,000 such products are on the market, a report released yesterday by the House Government Operations subcommittee on intergovernmental relations and human resources concluded that there was a "systemic breakdown in the agency's enforcement of the pre-market approval requirements of the law."

"Over the past several years, FDA has repeatedly disregarded its responsibility for removing from the market new drugs that it has not approved as safe and effective," said the subcommittee's chairman, Rep. Ted Weiss (D-N.Y.)

The report contended that the FDA's failure to enforce the law "effectively signals to pharmaceutical manufacturers and distributors that they need not involve the agency in their decision to market new drug products."

It cited FDA data showing "dramatic increases" in the numbers of such drugs being marketed in recent years. While companies reported an average of 161 unapproved new products annually between 1971 and 1976, the average rose to more than 500 a year between 1977 and 1983. In 1983 alone, the study said, there were more than 800 reports of unapproved new products on the market.

The study was prompted by the deaths of premature infants earlier this year who had received intravenous injections of a product called E-Ferol Vitamin E Aqueous Solution.

The product, which was recalled after the deaths were reported, had never been approved by the FDA, even though the agency said it had learned in November 1983 that the product was being marketed. A later FDA investigation found that the product was associated with 32 deaths before its recall in April.

FDA testimony before the Weiss subcommittee indicated that E-Ferol had erroneously been allowed to stay on the market because of an agency policy allowing certain unapproved new drugs to be marketed if they are similar to drugs marketed before 1962, pending completion of a long-term review of the various drug classes.

The agency has maintained that although their effectiveness has not been proven, this group of older drugs has shown few safety problems.

The subcommittee report recommended new procedures to identify and remove from the market all new drugs that have not received FDA approval.

In addition, it suggested that drugs be labeled to show that they have been approved for their intended uses.

The new FDA commissioner, Dr. Frank Young, told the subcommittee in September that the E-Ferol problem indicated a need for "significant revision" of the agency's enforcement policies. "It no longer appears to be reasonable to presume the safety of a new drug product simply on the basis of its being 'related' to a pre-1962 prescription drug."

Young said the FDA plans to start taking action against "any unapproved, newly marketed or changed prescription drug product" if it differs in any way from pre-1962 products. The agency has also said it will require adverse-drug reports on all products, regardless of whether they have been approved.

The committee complained that while the new policy "addresses the future marketing of unapproved new drugs," the agency still has not proposed a plan for dealing with the thousands of unapproved new drugs already on the market.

An agency spokesman yesterday denied that that was the case.