Fat-Dissolving Injection: Downtime
Some of the products described on this page have not been approved as pharmaceuticals in Japan. They are imported personally under the responsibility of the treating physician, and they are not guaranteed to have the same efficacy and safety as domestically approved medications. In some cases, no approved medication with the same active ingredient exists in Japan. If a health problem occurs, it will not be covered by Japan's Relief System for Sufferers from Adverse Drug Reactions. Safety information from other countries differs from product to product. Before undergoing treatment, be sure to receive a thorough explanation from your doctor.
- Downtime at a glance
- Recovery timeline: treatment day to final result
- Common symptoms
- When can I do what? (Daily-life restrictions)
- Pain and anesthesia
- Tips for a smoother recovery
- Risks and side effects (the honest version)
- Spacing and combining with other procedures
- Who it may suit / who should be cautious
- Frequently asked questions
Downtime at a glance
Swelling, puffiness, and bruising under the chin and similar areas for a few days to a week. Easy to hide with a mask (individual results vary).
Typical downtime is A few days to 1 week (strong swelling and puffiness tend to peak at 2–3 days), and most people feel comfortable being seen in public after Often possible the same day or the next day (wear a mask if strong swelling bothers you). Results vary from person to person. How much swelling or bruising appears varies from person to person, depending on constitution and the extent of treatment.
Recovery timeline: treatment day to final result
Swelling, puffiness, and warmth tend to appear right after the injection. You may also feel a prickling pain or tenderness. The injected area can look puffed up, but this is generally attributed to the solution and temporary inflammation. On treatment day, keep makeup minimal, avoid strenuous exercise, alcohol, and soaking in the bath, and take it easy.
Swelling and puffiness tend to peak around this time. Some people start to notice bruising. Your jawline may look blurred and the area may hurt when pressed, but this usually settles within a few days. A mask makes this stage easy to cover naturally.
Strong swelling usually starts to subside and puffiness eases around this time. Any bruising will shift toward blue or purple tones. Some firmness or lumpiness may remain, but avoid massaging the area forcefully.
For most people, noticeable swelling settles down around this time. Bruises fade, turning yellowish along the way. The fat-reducing change is said to appear gradually from here on, so judging the results comes a little later.
Swelling and puffiness have mostly resolved by now, and bruising is usually no longer noticeable. Downtime from the procedure has largely settled, and some people begin to notice a change in their jawline — though how it feels varies from person to person.
The broken-down fat is said to be gradually cleared from the body, with changes starting to show around this time. One session often does not produce a dramatic change, and it is common to refine the result little by little over multiple sessions.
It is generally said that most people approach their goal over multiple sessions (typically a few). The number of sessions and the interval between them depend on the area, the solution, and the amount of fat, and vary from person to person, so we recommend planning together with your doctor.
Bars show approximate swelling levels (individual results vary).
Common symptoms
| Symptom | Likelihood | When it appears | How long it lasts | Notes |
|---|---|---|---|---|
| Swelling and puffiness | High | Same day (immediately after injection) | 2–5 days (may linger for about a week in some people) | This is generally said to be an inflammatory response to the solution. It tends to be more noticeable in fat-rich areas such as under the chin, and varies from person to person |
| Bruising (black-and-blue marks) | Medium | Same day to the next day | 1–2 weeks | Can occur when the needle touches a small blood vessel. Most bruises turn yellowish and gradually fade |
| Pain, tenderness, and warmth | High | Same day to the next day | 2–4 days | You may feel soreness when pressing, or a tingling, throbbing sensation. How likely this is differs by the type of solution used |
| Firmness or lumpiness | Medium | A few days later | 1 to several weeks (rarely longer) | The area may temporarily feel firm to the touch while the fat breaks down. If it persists for a long time, consider seeing your doctor |
| Itching and redness | Low | Same day to a few days | A few days | This may be a reaction to the solution. See a doctor if you develop intense itching or spreading redness |
| Fatigue or mild feverishness | Low | Same day to the next day | 1–2 days | May occur after larger-area injections. See a doctor if a high fever or severe symptoms persist |
When can I do what? (Daily-life restrictions)
| Activity | Typically OK from | Key point |
|---|---|---|
| Makeup | From the next day (same day may be fine if you avoid the injection sites) | On treatment day, keep makeup off the injection sites to help prevent infection through the needle marks. Redness and bruising are easy to cover with foundation or concealer |
| Face washing | Same day (gently) | Wash without rubbing or irritating the skin, and do not massage the injection sites firmly |
| Shower and bathing | Shower from the same day; soaking in the bath from the next day onward as a guideline | Long or hot baths on treatment day can boost circulation and intensify swelling and bruising, so avoid them |
| Alcohol | From the next day onward (avoid on treatment day) | Alcohol promotes blood flow, which can easily worsen swelling and bruising, so it is safest to skip it on treatment day |
| Exercise | Light exercise from the next day; strenuous exercise from around 2–3 days after | Strenuous exercise on treatment day boosts circulation and can add to the swelling. It is safer to skip even light exercise on the day itself |
| Sauna and hot-stone spa | From 2–3 days after (once the swelling has settled) | Heavy sweating and increased circulation can prolong swelling and puffiness |
| Sleeping face-down or strong pressure | Avoid for the first few days | Pressure on the injected area can affect how the solution spreads and worsen bruising, so be mindful of your pillow position on treatment day |
| Firm massage and facial treatments | Follow your doctor's instructions (wait a few days and see how things go) | Do not knead the area firmly on your own judgment; massage lightly only if it is recommended |
Pain and anesthesia
The typical pain level is Mild. Some people have the treatment without anesthesia, but if you are worried about pain, topical numbing cream or cooling may be offered to ease it. Options differ by medical institution You may feel a small prick at injection, and a stinging sensation or warmth as the solution spreads. Tenderness when pressing the area can linger for about 2–4 days afterward, but for most people it is generally said to stay within a range that does not significantly interfere with daily life. How much pain occurs differs by the type of solution, and sensitivity varies from person to person.
Tips for a smoother recovery
- Lightly cooling the injected area on treatment day — without overdoing it — is generally said to help ease swelling and warmth (follow your doctor's instructions)
- For the first few days, avoiding alcohol, strenuous exercise, saunas, long baths, and other activities that strongly boost circulation is said to help keep swelling and bruising from lingering
- Go easy on salt and stay adequately hydrated to keep puffiness from building up
- If bruising concerns you, talk to your doctor. If you bruise easily, letting the clinic know in advance is reassuring
- Get plenty of sleep and rest; sleeping with your head slightly elevated is said to help puffiness subside
Risks and side effects (the honest version)
- Downtime symptoms such as swelling, puffiness, bruising, and pain will occur (the degree varies greatly from person to person)
- Results vary from person to person; a single session may produce little noticeable change, and multiple sessions are often needed
- Firmness or lumps at the injection sites, asymmetry, or unevenness can occur temporarily
- In rare cases, allergic reactions, strong inflammation, or infection can occur
- Depending on the solution and injection technique, effects on nerves or blood vessels, or unexpected skin changes or sagging, are possible
- Ingredients, expected effects, and risks differ by type of solution, so it is important to receive an explanation of the product being used
- The above is general information. If you have a medical condition, allergies, or take medication, or if you are pregnant or breastfeeding, be sure to consult a doctor in advance
Spacing and combining with other procedures
Having the treatment at least 1–2 weeks before an important event such as a wedding or photo shoot makes it easier to attend with the swelling and bruising resolved. If you want a visible change, consider planning multiple sessions starting several months in advance For repeat treatment of the same area, an interval of about 2–4 weeks is generally recommended (this differs by solution and area). The next session is done after the previous swelling has settled. Follow your doctor's instructions for the specific interval
| Combined procedure | Timing | Wait time | Reason |
|---|---|---|---|
| Botox Injection (Jaw & Chin) | Same day OK | Same day, or on separate days (at your doctor's discretion) | These serve different purposes and are sometimes combined, but when done on the same day, the injection sites and amounts need to be adjusted, so follow your doctor's judgment |
| Hyaluronic Acid Filler | Wait required | About 1–2 weeks (at your doctor's discretion) | Doing both in nearby areas on the same day can make swelling and bruising overlap, making the course harder to assess. Same-day treatment may be possible for different areas, but an interval is often left |
| HIFU (High-Intensity Focused Ultrasound), Radiofrequency (RF), and Other Lifting Treatments | Wait required | About 1–2 weeks (at your doctor's discretion) | Combining with heat-based treatments can intensify swelling and puffiness, so it is safest to wait until the injection-related swelling has settled |
| Liposuction | Not recommended | Leave at least several weeks and consult your doctor | As a surgical procedure on the same area, its purpose and downtime differ greatly, and combining the two close together tends to complicate recovery, so leave a generous interval and decide together with your doctor |
| Laser & Light Treatments (Facial) | Wait required | About 1–2 weeks (at your doctor's discretion) | Applying heat-based stimulation while the injection sites are still inflamed can raise the risk of swelling and pigmentation, so it is safer to wait until the swelling has gone down |
Who it may suit / who should be cautious
May suit you
- Those bothered by localized fat under the chin (a double chin) or along the jawline
- Those who want gradual change without surgery and with limited downtime
- Those who want to refine fat in smaller areas such as the cheeks or around the mouth
- Those not ready for liposuction who would like to try an injection-based approach first
Consider carefully
- Those who want to reduce a large amount of fat over a wide area at once (a surgical procedure may be more suitable)
- Those with allergies to any ingredient in the solution to be used
- Those who are pregnant or breastfeeding
- Those with skin problems or an infection in the planned injection area
- Those with serious medical conditions, or those expecting immediate dramatic results (consult a doctor in advance)