In a letter released last week, the FDA warned against batches of the wrinkle treatment sold by wholesalers controlled by Canada Drugs, which was previously linked to fake cancer medicines.
It said the Botox has not been approved by the FDA so the agency cannot assure its effectiveness or safety - and warned doctors against buying from places other than licensed U.S. pharmacies.
Dangers: The FDA has warned 530 medical practices they might have received fake batches of Botox
The warnings refer to injectable treatments that have been distributed through medical practices and not directly to patients.
It is the fifth time this year that the agency has alerted doctors to unapproved, overseas drugs, most of which have been sold by Canada Drugs' companies.
Warning: The Botox has not been approved by the FDA so they cannot guarantee that it is safe
In February, the agency first told 19 medical practices that they had bought a cornstarch and acetone-based imitation of Avastin medicine from the network.
On three more occasions the FDA issued warnings about counterfeit Avastin and Altuzan. The alerts were also primarily targeted at drugs distributed by Canada Drugs, an internet-based company.
Canada Drugs, which is based in Winnipeg, has profited for years by selling cheaper versions of drugs from price-controlled markets to American customers and doctors.
Even when the medicines are authentic, the FDA deems them illegal because they have not been approved by the agency.
The fear is that the practice could eventually lead to U.S. customers receiving fake medicines.
In September, the agency tried to shut down Canada Drugs' website in September but was unsuccessful. It continues to investigate the company, officials said.
A request for comment from the drug distributor was not immediately returned.
Drug shortages have increased the financial incentives for some pharmacies to provide fake or illegally imported drugs.
Site: The warnings refer to Canada Drugs - an internet-based company that has been linked to fake cancer drugs. It makes cheaper versions of drugs and these are not approved by the FDA
In October, the FDA ordered operators of about 4,100 websites to immediately stop selling unapproved medications to U.S. consumers.
The vast majority of those sites were operated by Canada Drugs. The site was still operating Friday.
Genuine Botox is made by Allergan Inc., based in Irvine, California. Avastin is made by Roche Holding AG's Genentech unit.
Read more: http://www.dailymail.co.uk/news/article-2252867/FDA-warns-hundreds-medical-practices-flood-fake-dangerous-Botox.html#ixzz2G5cym7g2
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