Morning Sickness Drug Back On Shelves This May After 30 Years Off Market

  @rpalmerscience on April 09 2013 2:23 PM

Nauseated pregnant women will soon have cause to celebrate: For the first time in 30 years, there will be a drug for morning sickness back on pharmacy shelves in the U.S.

On Monday, the U.S. Food and Drug Administration approved the release of a drug called Diclegis, a new version of a pill that was previously sold under the name Bendectin. The drug is expected to be widely available by the end of May, according to manufacturer Duchesnay USA.

“Many women experience nausea and vomiting during pregnancy, and sometimes these symptoms are not adequately managed through recommended changes in diet and lifestyle,” FDA official Hylton V. Joffe said in a statement Monday. “Diclegis is now the only FDA-approved treatment for nausea and vomiting due to pregnancy, providing a therapeutic option for pregnant women seeking relief from these symptoms.”

Some of the non-medicinal options for treating morning sickness include avoiding foods that cause nausea, and taking ginger, vitamin B6 or vitamin B12. For some women, this clears the problem up; for others, it does not. In rare cases, nausea and vomiting can become so severe that the mother has to be hospitalized. This condition, called hyperemesis gravidarum, recently afflicted the Duchess of Cambridge Kate Middleton, and might have contributed to the death of English novelist Charlotte Bronte.

Diclegis was tested in a trial of 261 pregnant women experiencing nausea. After two weeks, the women taking the drug saw a greater improvement in their symptoms than the group taking placebo. The drug is taken daily, on an empty stomach and usually at bedtime. The most common side effect is drowsiness, so expectant moms should avoid taking it right before driving or taking their bulldozer out for a spin.

A previous formulation called Bendectin, was approved by the FDA in 1956. The drug was reformulated in 1976 to remove an ingredient called dicyclomine hydrochloride, which the FDA found did not contribute to the drug’s overall effectiveness.

Starting in the late 1970s, lawsuits starting piling up against the drug’s manufacturer, Merrell Dow, claiming Bendectin caused birth defects. Though Merrell Dow maintained that the drug was never proved hazardous, and the FDA never recalled it, a wave of bad press and mounting litigation and insurance costs prompted the drug maker to pull Bendectin off the shelf in 1983.

Even at the time, the evidence for Bendectin’s supposed ill effects was sketchy. There were some studies that established a link between the drug and birth defects that asked mothers of malformed and normal children about their pregnancies, but these may have fallen prey to unconscious biases.

“Psychologists have shown … that people are more likely to recall factors associated with an abnormal event than with a normal one,” the New York Times wrote in 1983. “Thus, mothers of defective babies may have been more likely than mothers of normal children to remember and report that they took Bendectin during pregnancy.”

When some studies corrected for this bias, the link between Bendectin and birth defects vanished.

There was also never very much clarity about how exactly Bendectin was supposed to have damaged fetuses. Parties have claimed that the drug caused damage in just about every system of the body, from respiratory defects to musculoskelatory problems to cancer.

“Doctors know of no teratogen -- an agent that causes birth defects -- that produces anything resembling this variety of problems,” the New York Times wrote.

One of the expert witnesses in several lawsuits against Merrell Dow was Australian doctor William McBride, who first brought to light the birth defects associated with the anti-nausea drug thalidomide, and published a paper linking Bendectin (referred to by its U.K. commercial name Debendox) to birth deformities in rabbits in 1982. But in 1993, McBride was found to have manipulated the results of experiments, and was removed from Australia’s medical registry after a tribunal deemed his conduct “reprehensible.”

Whistleblower Phil Vardy, who worked for McBride, said that the doctor’s published data on the Debendox rabbit experiments didn’t match the original laboratory books. The doctor had added fictitious animals and changed the dosages used.

“Science is based upon the pursuit of truth, so you can't imagine reality into place, you can't construct reality into place,” Vardy told the TV program Australian Story in 2001. “And here was Bill 'cooking the books', so to speak, to try and prove his case.”

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