How Long Does Botox Last for Crow's Feet & What are Injection Sites?

What is Botox?

Botox is a muscle relaxing medicine that is formulated by Allergan Pharmaceuticals. This neuromuscular paralytic agent is made of botulinum toxin and excipients (human albumin and sodium chloride) that are extracted from the Hall strain of Clostridium botulinum left to ferment with glucose, casein hydrolysate, and yeast extract. Once isolated and purified, the toxin is vacuum-dried and sterilised to create a white powder that must be reconstituted with sterile, preservative-free saline solution (9mg/mL sodium chloride solution) prior to intramuscular administration. The prepared botulinum toxin solution must be transparent, free from any suspending particles, and with a colourless to slight yellowish hue.

How is Botox used to treat crow’s feet?

Due to its potent muscle relaxing activity, Botox is used in the medical field to relax painfully contracting muscles such as cervical dystonia, hemifacial spasms, and limb spasticity. But, it is most well-known as a permanent fixture in the field of aesthetic medicine as it can be used to soften the appearance of facial lines like crow’s feet and forehead lines caused by muscle movements. Once it is administered, the injected muscles will temporarily relax, resulting in short-term correction of dynamic wrinkles.

What are the injection sites?

Following the careful preparation of the botulinum toxin solution, a certified aesthetician can then slowly inject the reconstituted solution approximately 1.5cm to 2.0cm temporal to the lateral canthus and just temporal to the orbital rim. These injection sites maintain a safe distance from the muscles that control eyelid movement and reduce the risk of eyelid ptosis (drooping). Aestheticians are recommended to inject 4 units of botulinum toxin in each of the 3 injection sites per side in the lateral orbicularis oculi muscle—the total dose is 24 units of Botox. The needle tip must be bevel up and away from the eye throughout the procedure to minimise the risk of injuries.

How long does Botox last for crow’s feet?

Patients should be able to notice the reduced appearance of crow’s feet approximately 3 days following the treatment session. This aesthetic improvement will then last for about 4 months; however, this duration of action varies on an individual basis depending on patients’ age, health status, skin condition, and lifestyle habits. Patients should not return for maintenance treatment session more frequently than every 3 months.