By Lynne Adkins

PHILADELPHIA (CBS) — The CDC is monitoring use of an anti AIDS pill in four cities, one being Philadelphia.

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The Strawberry Mansion Health Center is one of the facilities where patients will be monitored for use of Truvada, a pre-exposure prophylaxisis, or PrEP.

The medication is given to people at high risk to prevent them from becoming HIV positive.

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Dr. Dawn Smith, an epidemiologist at the Centers for Disease Control and Prevention says the pill is taken daily.

“We will be able to see over time how long people want to stay on PrEP. When they get monitored for PrEP, according to our guidelines, we’ll be able to see how well they’re doing on their PrEP. It’s the same follow up you get for any kind of chronic medication or intervention you would get in a clinic setting.”

While only four sites will be monitored, the medication is available nationwide.

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