BOSTON — The owner of a South Shore spa linked to more than a dozen cases of botulism has pleaded guilty in federal court to performing illegal injections using unapproved Botox.
Rodrigo de Medeiros Siqueira, 33, of Quincy, the owner of Rodrigo Beauty Inc. in Milton, pleaded guilty to one count of misbranding of a drug after shipment in interstate commerce with the intent to defraud or mislead, U.S. Attorney Leah Foley said in a statement on Friday.
U.S. District Court Judge Richard Stearns scheduled sentencing for Aug. 12.
Medeiros Siqueira was arrested and charged by complaint in October.
Prosecutors said Medeiros Siqueira admitted to injecting clients at his Milton spa with unapproved botulinum toxin obtained from illegitimate sources outside the United States, resulting in numerous severe cases of botulism.
In June, a longtime customer of Rodrigo Beauty on Granite Avenue in Milton told Boston 25 that she went to the hospital when she began feeling dizzy after having “a full face of Botox” at the spa.
“When I found out that it happened at the spa that I go to, it was like a nightmare,” the former customer said at the time.
The Department of Public Health began investigating. In June, state public health officials said 18 suspected cases of iatrogenic botulism were linked to Botox injections at Rodrigo Beauty.
Beginning in or around August 2022, prosecutors said Medeiros Siqueira offered various cosmetic injection procedures, including the injection of botulinum toxin prescription drugs, to clients of Rodrigo Beauty, despite not being licensed to prescribe, dispense, or administer prescription drugs or perform injections.
“Medeiros Siqueira falsely represented to clients that he was a licensed medical professional authorized to perform injections and made false statements to clients regarding the identity and source of the botulinum toxin products he was using for their injection procedures,” Foley said.
Beginning in or around late May 2025, prosecutors said numerous Rodrigo Beauty clients were diagnosed with botulism as a result of injections Medeiros Siqueira performed using unapproved botulinum toxin.
Botulism is a rare and dangerous illness that can result from, among other things, the injection of botulinum toxin.
Iatrogenic botulism is caused by botulinum toxin circulating in the blood and spreading beyond the injection site, potentially resulting in life-threatening symptoms, including blurred or double vision, drooping eyelids, slurred speech, and/or difficulty swallowing or breathing.
While botulinum toxin is generally safe when administered by trained medical professionals, prosecutors said improper dosing, administration technique, or use of non-FDA-approved products can result in severe cases of botulism.
Anyone who may have received services involving illegal injections or unapproved drugs or devices from Medeiros Siqueira or Rodrigo Beauty is urged to complete this form located on the FDA’s website.
Information about the status of the case is located on the U.S. Attorney’s Office website.
Medeiros Siqueira faces a sentence of up to three years in prison, one year of supervised release, and a fine of $250,000 or twice the gross gain or loss from the offense, whichever is greater.
This is a developing story. Check back for updates as more information becomes available.
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