All six have been hospitalized after receiving either cosmetic Botox to the face or Botox for sweating.
It is unclear whether the poisonings are caused by the preparation itself - botulinum toxin - or by an incorrect dosage. According to STPS, there is strong evidence that the victims were treated with unapproved preparations or by unauthorized persons.
The public is warned in a press release.
"If you are going to undergo cosmetic treatment, we recommend that you check the Swedish Board of Patient Safety's authorization register," the authority writes.
Anyone who has recently been treated with Botox and experiences symptoms of poisoning, such as double vision, speech problems or muscle weakness, should contact a doctor.
