WASHINGTON (AP) - Federal officials are encouraging generic drugmakers to reformulate their painkillers to make them harder to abuse, the latest in a string of steps designed to combat abuse of highly-addictive prescription pain drugs.

WASHINGTON (AP) Federal officials are encouraging generic drugmakers to reformulate their painkillers to make them harder to abuse, the latest in a string of steps designed to combat abuse of highly-addictive prescription pain drugs.

The Food and Drug Administration published draft guidelines outlining testing standards for harder-to-abuse generic painkillers. The agency has already approved five brand-name painkillers which are designed to discourage abuse. The current version of OxyContin, for example, is difficult to crush, discouraging abusers from snorting or dissolving the tablets to get high.

But these abuse-deterrent painkillers represent a small fraction of the market for opioid pain drugs, which is dominated by low-cost generics.

The FDA draft guidelines released Thursday outline studies needed to show that generic opioids have the same anti-abuse properties as their brand-name counterparts.