Of those, only Lotronex, a treatment for irritable-bowel syndrome in women, has been re-introduced.

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Lotronex was for preventing diarrhea, not constipation, but the doctors still may be shy about prescribing Zelnorm.

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One drug currently available, called Lotronex, affects the limbic system and has worked more successfully in women than men.

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However, the FDA recently made a rare decision to make Lotronex available to a small number of patients incapacitated by their disease.

FORBES

This imitates what happened with another Glaxo drug, Lotronex for irritable bowel syndrome, which was withdrawn because it caused bowel obstructions but then put back on the market with serious restrictions.

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Making matters more difficult for Novartis is the fact that the last drug for IBS, GlaxoSmithKline 's (nyse: GSK - news - people ) Lotronex, was recalled because of dangerous side effects.

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GlaxoSmithKline (nyse: GSK - news - people ), the world's second-biggest drugmaker, developed a medicine called Lotronex that treated IBS marked by diarrhea, but the drug was withdrawn from the market for safety reasons.

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