The U. S. Food and Drug Administration on Wednesday approved the first generic version of the controversial emergency contraceptive Plan B (levonorgestrel) tablets, 0.75 mg, or the Plan B morning-after contraceptive.

In a press release the FDA said currently the generic version is made by a unit of Watson Pharmaceuticals Inc., based in Corona, Calif. and is available by prescription only for women 17 years and younger.

Plan B, manufactured by Duramed Pharmaceuticals Inc., of Cincinnati, subsidiary of Barr Pharma, was first approved in 1999 for prescription use only for women of all ages. In 2006, it was approved for nonprescription use for women ages 18 and older and remained available as a prescription-only product for women ages 17 and under.

The new approval however allows the marketing of a prescription-only generic product for women ages 17 and under. The marketing exclusivity held by Duramed for the nonprescription use expires on Aug. 24 after which the generic version will become available for women 18 and older without a prescription.

Levonorgestrel has been shown to reduce pregnancy risk if taken within 72 hours after unprotected intercourse or a known or suspected contraceptive failure. However It is not effective in terminating an existing pregnancy nor does it protect against sexually transmitted diseases, including HIV infection.

The Bush administration had imposed an 18 year old age limit for women to use an over-the-counter brand-name version of the Plan B contraceptive which a federal judge in March, rolled back 17 years.