The findings have sparked a new look into how medication affects men and women differently.
Jeremy Popek is a pharmacist at the Medicine Shoppe.
He explains why men and women need different dosages of the same medication.
"Because they eliminate the medications at a different rate," he said.
Last year the FDA cut the suggested dose of Ambien in half for women.
"They need a lower dose to cause the same effect," Popek said.
That means for years women have been taking twice as much Ambien as they need.
That could lead to impairment in the morning when they get in a car to drive to work.
This realization sparked a conversation in the medical community about how important it is to custom fit a prescription to a patient.
"Medicine has to be tailored not only to each gender, but then to each person so it goes beyond just the gender," Popek said.
A person's medical history and health can also play a role in how their body accepts the medication.
"Certain drugs are metabolized through the liver, so if there's liver problems you need to lower the dose whether or not they are male or female," he said.
Popek said making sure the patient takes the right amount of any medicine is a team effort between doctors, pharmacists, and patients.
"The most important thing is communication so patients need to communicate with their doctors," he said.
Doctors need to recognize when a patient needs a lower dose and then communicate that to the pharmacist.
"We're the last people they see before they take the medicine, so it really comes down to a team effort," he said, "So that we're all on the same page and that will lead to better outcomes."
The FDA approved Ambien 20 years ago, but just last year recognized how it affected men and women differently.
Right now Ambien is the only prescription drug for which the FDA recommends different dosages based on gender.
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