Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of prescription and over-the-counter generic drug producer Hi-Tech Pharmacal (Nasdaq: HITK) are going downhill quickly today, losing as much as 21% following news of a competitor's drug being approved by the Food and Drug Administration.

So what: According to reports, Indian drug company Wockhardt today received FDA approval to market fluticasone, a corticosteroid used to treat allergic rhinitis and a generic version of GlaxoSmithKline's (NYSE: GSK) Flonase. "What's the problem?" you might be wondering. Hi-Tech Pharmacal also markets a generic version of fluticasone in the United States. In fact, fluticasone accounted for $23 million of the company's $56.9 million in total revenue during the second quarter, so today's approval could indeed be pivotal.

Now what: The great thing about generic companies is that they have a seemingly endless supply of drugs falling off patent. Unfortunately, when you sometimes have multiple companies competing for the same bone, you run into an issue like Hi-Tech has today. It remains to be seen how badly Hi-Tech's revenue stream will be affected by today's FDA ruling, but clearly this isn't good news and I completely understand the move lower. As of now I'm more than happy waiting this one out on the sidelines.

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