The effects of Botox usually last three to four months, though longevity varies by area treated, dosage, metabolism

https://www.scribd.com/document/1027456623/Botox-Cosmetic-A-Beginner-s-Guide-to-Treatment-Options-146439

The effects of Botox usually last three to four months, though longevity varies by area treated, dosage, metabolism, and lifestyle factors; maintenance sessions help sustain consistent results.