The Food and Drug Administration says it will continue to require tamper-resistant packages for nonprescription drugs, after concluding that they do not impose an unacceptable burden on the elderly.

The FDA said its finding that the benefits of tamper-resistant packaging outweigh any problems was based on a study of how much trouble 1,100 elderly people had in opening the packages.

The special packaging was ordered after the 1982 Tylenol poisoning deaths, in which the nonprescription pain relievers were found to have been tainted with cyanide.

The FDA said its study showed that most elderly people easily opened tamper-resistant packages in less than a minute without the use of scissors or other special tools.

The most difficult caps were "film wraps," which completely encase the product, and "shrink seals," which encase the bottle neck and cap. Nevertheless, the FDA said, those caps added only 25 to 50 seconds to the time needed to open the packages.

The study, conducted with the Consumer Product Safety Commission, was begun in 1983 after complaints that the packaging was unduly burdensome for the elderly.

The FDA said it would share the study results with the drug industry because of the finding that some closures were more convenient to open than others.