Table of Contents
- Why Skin Boosters Cause Side Effects
- Common Side Effects and How Long They Last
- Small Bumps
- Redness and Swelling
- Bruising
- Tenderness and Itching
- What the Evidence Shows
- Less Common Side Effects
- Lumps That Persist
- Infection
- Cold Sore Flare
- Allergic Reactions
- Rare but Serious: Injection into a Blood Vessel
- Who Is More Likely to Have Side Effects?
- Skin Booster Aftercare
- The First 24 Hours
- The First 48 Hours
- The First Two Weeks
- Planning Around Events
- Side Effects by Product
- When to Contact Your Doctor
- How to Lower Your Risk
- Frequently Asked Questions
- How long do skin booster bumps last?
- Can I go to work after a skin booster?
- Can I wear makeup after a skin booster?
- Is it normal to have a lump after a skin booster?
- Do side effects affect the final result?
Skin boosters are injected into the skin in many small points, so some short-term reactions are expected. Most are mild and settle within a few days. However, it helps to know what is normal, how long it usually lasts and which rare signs need a doctor straight away. This guide covers side effects that apply to most skin boosters, followed by aftercare steps and warning signs. If you would like a doctor to check whether a skin booster suits you, contact CLEO Clinic.
Why Skin Boosters Cause Side Effects
Most early side effects come from the injections rather than from the product itself. Each needle or cannula pass creates a tiny wound, and each small deposit of product lifts the skin slightly. As a result, redness, small bumps and mild swelling are common straight after treatment. In addition, some products, such as polynucleotides and hyaluronic acid, attract water, which can make the area look puffy for a day or two. For an overview of how the different types work, see our skin booster treatment page.
Common Side Effects and How Long They Last
| Side effect | What it looks like | Usual duration |
|---|---|---|
| Small bumps | Raised dots at each injection point | One to two days, sometimes longer |
| Redness | Pink or flushed skin over the area | Hours to a day or two |
| Mild swelling | Puffiness, often worse the next morning | One to two days |
| Bruising | Small blue or purple marks | Up to about a week |
| Tenderness or itching | Sore or itchy skin | A few days |
Small Bumps
Small bumps are the most noticeable side effect, especially after microdroplet or mesotherapy techniques. Usually, they flatten within one to two days as the product spreads into the skin. Thicker products and polynucleotides may leave bumps that take a little longer to settle.
Redness and Swelling
Redness often fades within hours, while mild swelling can last one to two days. Notably, swelling is more visible around the eyes, where the skin is thin.
Bruising
Bruises appear when a needle passes a tiny blood vessel. They are more likely in people who take blood thinners or certain supplements, and around the eyes or neck. In most cases, bruises fade within about a week.
Tenderness and Itching
The skin may feel sore, warm or slightly itchy for a few days. Still, this usually settles without treatment, and you should avoid scratching the area.
What the Evidence Shows
Published data on skin boosters support the view that most side effects are mild. For example, a 2026 randomised trial of NCTF 135HA on the neck reported that adverse events were mostly mild bruising and swelling, with no device-related serious events (Jiang et al., 2026). Similarly, Allergan Aesthetics states that most SKINVIVE side effects resolve within seven days. For polynucleotides, a 2026 expert review reported that granulomas and nodules had not been described in the published literature to date, although long-term data are limited (Rho et al., 2026). Nevertheless, several of these sources have links to manufacturers, so they should be read with care.
Less Common Side Effects
Lumps That Persist
Occasionally, a small lump remains after the other bumps have settled. Most soften over the following weeks. However, a lump that is still present after about two weeks, or one that is painful, red or growing, should be checked by your doctor.
Infection
Infection is uncommon. Signs include increasing redness, warmth, pain, swelling or pus a few days after treatment. Therefore, contact your doctor if you notice any of these, because early treatment matters.
Cold Sore Flare
Injections around the mouth can trigger cold sores in people who get them. For this reason, tell your doctor beforehand if you have a history of cold sores, because they may suggest preventive medicine.
Allergic Reactions
Allergic reactions are uncommon but possible. For instance, polynucleotide boosters such as Rejuran are made from salmon DNA, so they are not suitable for people with a fish allergy. Likewise, some hyaluronic acid products contain lidocaine. Seek urgent medical help if you notice swelling of the lips, tongue or throat, or difficulty breathing.
Rare but Serious: Injection into a Blood Vessel
This is rare, but it is the most serious risk with any injectable. In fact, Allergan warns that accidental injection into a blood vessel can cause serious, possibly permanent complications, including vision problems. Consequently, seek urgent help straight away if you notice severe or increasing pain, pale, white or dusky skin, or any change in vision after treatment. Because hyaluronic acid products can be dissolved with an enzyme, treatment should only be given by a trained doctor who can act quickly if a problem occurs.
Who Is More Likely to Have Side Effects?
Some people are more prone to bruising or swelling. For example, this includes people who take blood thinners, aspirin or fish oil, and those with thin skin or sensitive skin. Moreover, treating the under-eye area or neck carries a higher chance of visible bruising. Skin boosters are generally not given during pregnancy or breastfeeding, where there is an active skin infection or with an allergy to any ingredient.
Skin Booster Aftercare
The First 24 Hours
First, avoid touching, rubbing or massaging the area unless your doctor tells you to. Next, wash your face gently with a mild cleanser and lukewarm water. Avoid makeup for about 24 hours so the injection points can close. In addition, sleeping with your head slightly raised on the first night can reduce puffiness.
The First 48 Hours
For the first 24 to 48 hours, avoid strenuous exercise, saunas, steam rooms, hot baths and alcohol. Similarly, pause strong skincare such as retinoids, exfoliating acids and scrubs until the skin has settled. A cold compress wrapped in a clean cloth can ease swelling. Finally, use sunscreen every day, as our guide to physical vs chemical sunscreen explains.
The First Two Weeks
Avoid facials, lasers and other treatments on the same area unless your doctor has planned them. Likewise, keep follow-up appointments, because your doctor will check how your skin has responded before the next session. To learn how long results last and when to book a top-up, read how long a skin booster lasts.
Planning Around Events
Because bumps and bruises can take a few days to settle, avoid booking treatment just before a wedding, photoshoot or holiday. Our guide to avoiding skin booster injections before events explains how far ahead to plan.
Side Effects by Product
Side effects are similar across most boosters, although each product has a few points of its own. For product-specific guides, read NCTF 135HA side effects and aftercare, SKINVIVE side effects and aftercare and Rejuran side effects and aftercare. In addition, because boosters behave differently from fillers, our guide to skin boosters vs dermal fillers explains why their risks also differ.
When to Contact Your Doctor
Most side effects are mild and expected. However, contact your doctor if bumps or swelling last longer than a week, if bruising is severe or if you notice signs of infection. Seek urgent help straight away for severe pain, pale or dusky skin, vision changes or signs of a serious allergic reaction.
How to Lower Your Risk
Choosing a doctor-led clinic and a genuine product are the most important steps. You can check a doctor’s registration with the Malaysian Medical Council. In Malaysia, injectable skin boosters are regulated as medical devices, so you can check registration with the Medical Device Authority (MDA). Also, ask to see the sealed box, batch number and expiry date before treatment. To discuss your options with a doctor, book a consultation with CLEO Clinic.
Frequently Asked Questions
How long do skin booster bumps last?
Most bumps flatten within one to two days. Thicker products and polynucleotides may take a little longer.
Can I go to work after a skin booster?
Most people return to work the same day or the next day. However, bumps and redness may be visible for a day or two.
Can I wear makeup after a skin booster?
Wait about 24 hours so the injection points can close. After that, use clean brushes or sponges.
Is it normal to have a lump after a skin booster?
Small lumps are common in the first few days. However, a lump that lasts beyond about two weeks, or one that is painful or red, should be checked by your doctor.
Do side effects affect the final result?
No. Normal bumps, redness and bruising do not affect the final result, which builds over the following weeks.