Depending on the dose and area injected, anti-wrinkle injections generally last up to 3-4 months. The only cases where it may not last the full 3-4 months are when:
- The full recommended dose was not injected. This could be due to patient budget, or if a patient wants to still have movement after injection.
- It is an area where it needs to be treated with a conservative approach, to prevent adverse events after injection. For example, the forehead muscle raises the eyebrows up. If someone has a weak muscle and is heavy on their upper eyelids, if too much product is injected, the patient could potentially suffer from eyebrow ptosis (droop).
- In the rare instance, the patient could develop resistance to the product.