Study Finds Increased Risks from Botox in Patients with Chronic Conditions

A U.K. study has found that people living with chronic illnesses face a markedly higher chance of complications following cosmetic botulinum toxin injections, widely known as Botox. Conducted by Anglia Ruskin University researchers, the study surveyed 919 adults who had undergone these treatments for aesthetic reasons and was published in Aesthetic Surgery Journal.

The findings show that individuals with underlying medical conditions such as type 1 diabetes, thyroid disorders, chronic migraine, and various skin diseases are substantially more vulnerable to adverse outcomes from Botox procedures. Participants with type 1 diabetes were found to be 92 times more likely to suffer nausea following treatment, while those with thyroid disorders or chronic migraine faced roughly a tenfold increase in the same symptom.

Additional complications linked to pre-existing health issues included persistent headaches, bruising, muscle weakness, and eyelid droop, medically referred to as ptosis. The study noted that cataract patients were 30 times more likely to experience headaches after an injection, whereas those with prior facial injuries showed a 21-fold greater risk of losing facial expression.

Botulinum toxin injections remain among the most frequently performed cosmetic interventions in the U.K., with around 900,000 treatments taking place annually. Previous research estimated that side effects such as swelling, pain, and headache appear in about 16 percent of cases. However, the new study provides the clearest evidence yet about which groups are the most susceptible to complications.

In response to these findings, the authors recommend that botulinum toxin injections only be administered by medically qualified professionals—such as doctors registered with the General Medical Council, maxillofacial dentists, or senior prescribing nurses—working in environments regulated by the Care Quality Commission.

Co-lead author Professor Lee Smith emphasized that these results challenge assumptions about the simplicity of cosmetic Botox treatments. “This national study, the largest patient-reported botulinum toxin safety analysis to date, exposes the myth that botulinum toxin is a trivial cosmetic procedure,” he said. He added that safe practice “requires not just injection skill but diagnostic discernment, psychological insight, and systemic medical understanding.”