After masseter Botox, the most important thing is to stay upright for three to four hours and avoid touching or pressing on your jaw for the rest of the day. Beyond that first window, your aftercare shifts to protecting your results over the coming weeks, including changing how you eat and when you exercise. Here’s what to do (and avoid) from the moment you leave the clinic through your next appointment.
The First 24 Hours
Stay upright for at least three to four hours after your injection. Lying down too soon can cause the product to shift away from the masseter muscle, potentially weakening nearby muscles you didn’t intend to treat. If your appointment is in the afternoon, plan to stay seated or standing through the evening before bed.
Don’t rub, massage, or press on your jaw for at least 12 hours, and ideally the full first day. This includes facials, face massages, and even absent-minded jaw rubbing. Pressure on the injection site can nudge the product into surrounding muscles like the risorius or zygomaticus major, which control your smile. If that happens, you could end up with a temporarily asymmetric grin until the effects wear off.
Skip hot showers, saunas, and steam rooms for about 24 hours. Heat increases blood flow to the face and can contribute to bruising or cause the product to migrate from where it was placed. A lukewarm shower is fine.
Exercise and Physical Activity
Wait at least 24 hours before doing anything strenuous. Running, weight lifting, hot yoga, and similar activities all spike blood flow to the face and create pressure changes that can move the product away from its target. Light walking is fine on the day of treatment, but save the real workouts for the next day at the earliest.
How to Sleep After Treatment
Sleep on your back the first night. Side sleeping and face-down sleeping press directly into the jaw area, and the risk of product migration from pressure is highest during these initial hours. If you’re not a natural back sleeper, propping pillows on either side of your head can help keep you from rolling over.
After 24 hours, side sleeping is generally considered low risk. If you want extra assurance, waiting a full 48 hours before returning to your normal sleep position is an even safer approach. After that two-day window, your sleeping position won’t affect how well the treatment works or how long it lasts.
Chewing and Diet Changes
This is the aftercare step most people overlook, and it matters more for masseter Botox than for cosmetic Botox in other areas. The masseter is a chewing muscle, and like any muscle, it grows when you work it hard. Chewing gum, crunching ice, tearing through beef jerky, or eating very chewy foods all exercise the masseter and can counteract your results over time.
For the first several weeks after treatment, avoid gum chewing entirely. Going forward, reducing gum use as much as possible will help your results last longer. You don’t need a liquid diet or anything extreme. Just be conscious of habitually tough or chewy foods, especially in the weeks right after each session when the muscle is beginning to relax and shrink.
When You’ll Feel and See Results
If you got masseter Botox for jaw clenching, teeth grinding, or TMJ pain, you’ll likely notice relief within 7 to 10 days. The tension in your jaw gradually fades as the muscle loses its ability to clench at full force. Many people notice they’re waking up with less soreness or fewer headaches in that first week or two.
If you’re after jawline slimming, patience is key. The aesthetic change is much slower because the muscle needs time to physically shrink from disuse. Here’s roughly what to expect:
- Days 1 to 7: Clenching eases up and the jaw feels less tight or sore, but no visible change yet.
- Weeks 6 to 12: The slimming effect becomes visible, especially in photos and your side profile.
- Around 3 months: Peak aesthetic results. This is when the jaw looks its most sculpted.
Don’t panic if your face looks the same after two weeks. The functional relief comes quickly, but the visual reshaping takes the full two to three months to develop.
Side Effects to Watch For
Mild bruising, slight swelling, or tenderness at the injection site are all normal and typically resolve within a few days. Some people feel a strange sense of weakness when they bite down hard, which is actually the treatment working as intended.
The side effect that catches people off guard is smile asymmetry. If the product migrates into the muscles responsible for pulling your lips into a smile, one side of your face may look different from the other when you grin. This is temporary and resolves as the effects wear off, but it’s one of the main reasons the “don’t touch your jaw” rule matters so much in the first day.
Difficulty swallowing or significant muscle weakness beyond the jaw area are not typical. If you experience either, contact your provider.
Scheduling Your Next Session
Masseter Botox isn’t a one-and-done treatment. Most people need a follow-up every 3 to 4 months initially. Over time, as the muscle stays relaxed and gradually loses bulk, you can often stretch that interval to every 4 to 6 months.
If you’re treating bruxism or TMJ symptoms, a consistent schedule of roughly every 3 months tends to work best for keeping symptoms from creeping back. If your primary goal is jawline slimming, spacing may be more flexible, especially after the first few rounds when the muscle has already reduced in size. The best guide is your own body: if your clenching hasn’t returned and your jawline still feels soft, you can hold off on rebooking. Let your symptoms lead, not a rigid calendar.