What are the reactions after receiving a slimming facial injection?

Jan 24, 2025 Source: Cainiu Health
Disease description:

I am 28 years old this year. After receiving the slimming injection for my face, I started worrying about whether adverse reactions might occur. I would like to know the normal reactions that may appear after receiving a facial slimming injection.

Doctor's answer (1)
Dr. Chen Lu

Common reactions after receiving a jawline slimming injection typically include localized swelling, mild pain, weakened masseter muscles, and facial stiffness.

1. Localized swelling: After the injection, the injection site may experience slight swelling due to irritation from the medication and the injection process itself. This swelling is usually most noticeable within the first one to two days following the injection, representing a normal inflammatory response by the body, which will gradually subside.

2. Mild pain: Most individuals will experience some degree of pain following the injection. This is because the injection process can irritate the skin and muscle tissues. The discomfort is usually most evident for several hours to one or two days after the injection and will subsequently diminish gradually.

3. Weakened masseter muscles: The primary component of the slimming injection is botulinum toxin, which acts on the masseter muscles, blocking nerve impulses between nerves and muscles, thereby relaxing the over-contracted masseter muscles, resulting in temporary muscle weakness.

4. Facial stiffness: For a period following the injection, some individuals may feel slight facial stiffness and find their expressions less natural. This occurs because the botulinum toxin might somewhat affect the surrounding facial muscles while taking effect. However, this condition is generally mild and tends to improve gradually within two to four weeks after the injection, with muscle adaptation and metabolism of the drug, eventually returning to normal.