What are the side effects of瘦脸针?
Mar 13, 2025
Source: Cainiu Health
Dr. Chen Lu
Introduction
In general, "瘦脸针" (slimming facial injection) refers to botulinum toxin type A for injection. It works by injecting the botulinum toxin type A preparation into the muscle tissue, blocking the nerve impulses between nerves and muscles, thereby relaxing over-contracted muscles and achieving the effect of facial slimming. Possible side effects may include local soreness or distension, unnatural smile, weakened chewing ability, facial asymmetry, and difficulty swallowing.
Generally, "slimming injection" refers to Botulinum Toxin Type A for injection. It achieves a face slimming effect by injecting Botulinum Toxin Type A to block nerve impulses to the muscles. The usual reference price for Botulinum Toxin Type A injection ranges from 1000 to 5000 yuan per session, and visible improvement is typically observed within 1 to 3 months after the procedure. Possible side effects of Botulinum Toxin Type A injection may include localized soreness, unnatural smile, weakened chewing ability, facial asymmetry, and difficulty swallowing. Detailed explanations are as follows:
1. Localized Soreness
After injection, the medication acts locally and may stimulate the muscles and surrounding tissues. Localized soreness typically appears within 1-2 days after injection and usually lasts about a week. This discomfort will gradually subside as the body adapts to the medication.
2. Unnatural Smile
The slimming injection targets the masseter muscles. If the dosage slightly deviates, it may cause imbalance in the strength of the bilateral masseter muscles. As a result, facial muscles may move in a dis-coordinated manner when making facial expressions, causing the smile to appear unnatural. This condition generally improves once the effect of the medication stabilizes.
3. Weakened Chewing Ability
Botulinum toxin paralyzes the masseter muscles and reduces their contractile ability. When the masseter muscles weaken, sufficient force for chewing may be lacking. This is more noticeable within the first 1-2 weeks after injection. With time, as the masseter muscles adapt to the new condition, chewing ability may gradually recover.
4. Facial Asymmetry
Due to inaccurate injection placement or dosage, the degree of atrophy in the bilateral masseter muscles may differ, resulting in uneven facial size and noticeable asymmetry. This is a relatively significant aesthetic issue that requires timely intervention and adjustment.
5. Difficulty Swallowing
If the medication spreads to adjacent muscles involved in swallowing, it may affect their normal function, leading to coordination problems during swallowing and causing difficulty swallowing. This situation is relatively rare but should be taken seriously.
It is recommended to choose a reputable medical facility and a qualified physician for the injection to reduce the risk of side effects caused by improper procedures. Additionally, strictly follow the physician's instructions and avoid arbitrarily increasing the injection dosage or shortening the injection interval.
