May 1, 2001

SOURCE: Watson Pharma, Inc.

FLORHAM PARK, N.J., The Following is Being Issued By Watson Pharma, Inc.:

Hypothyroidism, a disease in which the thyroid gland does not produce sufficient thyroxine, affects up to 24% of the older population(1), most of them women. Symptoms range from cold intolerance and weight gain to cardiovascular disease and dementia. It is estimated that 8 million people are being treated with levothyroxine sodium(2). To date, Unithroid(TM) (levothyroxine sodium tablets, USP) is the first and only NDA-approved oral levothyroxine sodium product approved as safe and effective by the FDA, having demonstrated stability and consistent potency, as well as dose proportionality.

Levothyroxine sodium, a narrow therapeutic index (NTI) drug, is titrated in very small increments until the patient is optimized. From then on, the patient is generally on the drug for life and the dosage is retitrated from time to time. This makes it critical that patients have a product that is consistent in potency and bioavailability.

Unfortunately, according to the FDA, some levothyroxine sodium products have ``significant stability and potency problems, [failing] to maintain potency through the expiration date and tablets of the same dosage strength ... vary from lot to lot in the amount of active ingredient present(3).'' Since 1991, there have been at least 10 recalls of levothyroxine, involving 150 lots and 100 million tablets(3). Because levothyroxine sodium was available prior to the NDA approval process, it was not subject to the same strict regulations as FDA-approved drugs with New Drug Applications (NDAs)(4). Therefore, manufacturers were able to reformulate the product, which resulted in potency fluctuations of up to 30%(3). Potency fluctuations can cause serious health consequences. The FDA has stated that ``variations in product potency present actual safety concerns.(3)'' In a recent large-scale study, it was shown that approximately 40% of the participants who were on thyroid hormone had abnormal thyroid test results(1).

As a result of the problems stemming from levothyroxine sodium's inherent instability and the possible health consequences to the public, the FDA stated in August 1997 that ``no currently marketed orally administered levothyroxine sodium product has been shown to demonstrate consistent potency, and thus, no currently marketed orally administered levothyroxine sodium is generally recognized as safe and effective.(3)'' The FDA originally required that all manufacturers of levothyroxine sodium have a complete and approved NDA by August 2000. The deadline was extended 1 year, to August 2001. After that, any levothyroxine sodium product that fails to comply with the FDA's mandate may be subject to regulatory action(3),(4).

To date, only the manufacturer of Unithroid has received NDA approval. This means that there is only 1 levothyroxine sodium currently available that the FDA has approved as safe and effective, having demonstrated stability and consistent potency, as well as dose proportionality.

Watson Pharmaceuticals, Inc. has recently entered into an exclusive agreement with Jerome Stevens Pharmaceuticals to market Unithroid. Unithroid was previously produced under the names levothyroxine sodium and Thyrox(TM) for more than 10 years, with 1 billion tablets manufactured without a recall(5). Unithroid is available by prescription only and may be found at your local pharmacy. Patients with hypothyroidism should ask their physicians about their treatment options. Please see Safety Information below for risks associated with the use of Unithroid.

This press release may contain forward-looking statements relating to Watson's future business performance, which involve risks and uncertainties that cannot be predicted or quantified. Consequently, actual results may differ materially from those expressed or implied. Such risks and uncertainties include, among others, those detailed in Watson's Securities and Exchange Commission filings.

Watson Pharmaceuticals, Inc., headquartered in Corona, California, is engaged in the development, manufacture, and sale of proprietary and off-patent pharmaceutical products.

Safety Information

WARNING: Thyroid hormones, including UNITHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.

• Unithroid is contraindicated in patients with untreated thyrotoxicosis, acute myocardial infarction, uncorrected adrenal insufficiency, or hypersensitivity to any of its inactive ingredients
• Should not be used to treat infertility unless condition is associated with hypothyroidism
• Use with caution in patients with cardiovascular disease
• Adverse reactions are primarily those of hyperthyroidism due to overdose, such as palpitations, arrhythmias, heat intolerance, weight loss, tremors, nervousness, diarrhea, abdominal cramps, fatigue, headache, and menstrual irregularities
• Reactions to product excipients, such as rash or urticaria, may occur
• Partial hair loss that may occur during initial months of therapy is generally transient