Rejuran Side Effects: Why You Get Bumps and How Long They Last

The small bumps you see after Rejuran are a normal, expected part of the treatment. They form because the polynucleotide gel is placed in many tiny deposits just under the surface of the skin, and each deposit raises a little blister-like papule until it spreads out and is absorbed. For most people these bumps flatten noticeably within a few hours to a day, and are usually gone within about one to three days. Redness, mild swelling and occasional small bruises are also common. Bumps that last much longer, become painful or hot, or keep getting bigger are not typical and should be checked by your doctor.

This article explains why Rejuran causes bumps, which other side effects are normal, how to help your skin settle, and when a reaction needs medical attention.

Why Rejuran Leaves Bumps

Rejuran is usually injected superficially, into the upper dermis, using a technique often described as micro-injections or micro-papules. The doctor places a small amount of product at many points across the face, sometimes hundreds of them. Because the product is relatively thick and sits close to the surface, each injection point lifts the skin slightly, creating a raised dot that can look like a mosquito bite.

These bumps are partly a sign that the product has been placed at the intended depth. Over the following hours, the gel disperses into the surrounding tissue and the bumps soften. The skin's natural swelling response to many small needle punctures also adds to the effect in the first day.

How visible the bumps are depends on several things:

• Injection technique: manual injections with a needle often create more defined bumps than some injector devices or cannula techniques.
• Product version: formulations mixed with hyaluronic acid or anaesthetic may behave slightly differently.
• Skin type: thin or sensitive skin and lighter skin tones can show bumps and redness more clearly.
• Area treated: the cheeks often show bumps more than areas with thicker skin.

A Typical Recovery Timeline

Everyone heals a little differently, but a common pattern looks like this:

• Immediately after: many raised bumps, pinpoint bleeding spots and redness. The skin may feel tight or tender.
• A few hours later: bumps start to flatten. Redness often fades considerably by the evening.
• Day 1 to 2: most bumps are much less noticeable. Some may still be felt more than seen.
• Day 2 to 3: for most people the skin looks close to normal, aside from any small bruises.
• Up to a week or so: bruises, if present, fade gradually. Occasionally a few small bumps persist a little longer, especially in thin skin.

If you are planning social events, work presentations or photos, it is sensible to allow at least two or three days after treatment, and longer if you bruise easily.

Other Common Side Effects

Besides bumps, the following effects are generally considered normal and temporary:

• Redness: usually settles within hours to a day.
• Swelling: mild puffiness, especially around the eyes if that area was treated.
• Bruising: small bruises at some injection points, which can take several days to a week or more to fade.
• Tenderness: the skin may feel sore to touch for a day or two.
• Pinpoint scabs: tiny marks at needle entry points that heal quickly.

Discomfort during treatment is also worth mentioning. Rejuran is known to be one of the more uncomfortable skin boosters. Numbing cream helps, and some product versions include a local anaesthetic.

Less Common and Rare Side Effects

Serious problems after Rejuran are uncommon, but it is important to know what they look like:

• Persistent nodules: firm lumps that do not settle after a couple of weeks. These may relate to technique, product placement or an individual reaction.
• Infection: increasing redness, warmth, pain, swelling or pus, sometimes with fever, usually developing a few days after treatment.
• Allergic reaction: itching, hives, widespread swelling or, very rarely, difficulty breathing. Mention any fish or salmon allergy before treatment.
• Acne or rash flare: some people notice breakouts or irritation, particularly if they already have active acne or sensitive skin.
• Pigment changes: people prone to post-inflammatory hyperpigmentation may develop temporary darker marks, especially if they get sun exposure soon after.

Because the evidence base mainly consists of clinical experience and relatively small studies, exact rates of these complications are not well established. In general, they are considered uncommon when treatment is carried out by a trained practitioner using a genuine product.

How to Help Your Skin Recover

Aftercare advice varies between practitioners, so always follow the instructions you are given. Commonly recommended steps include:

1. Avoid touching, rubbing or pressing the bumps. Let them settle on their own.
2. Skip makeup for the rest of the day, or as advised, to reduce the risk of infection.
3. Use a gentle cleanser and simple, fragrance-free moisturiser for a couple of days.
4. Avoid strong actives such as retinoids, exfoliating acids and scrubs for a few days.
5. Stay away from saunas, hot baths, intense exercise and alcohol for at least a day or two.
6. Protect your skin from the sun and use a broad-spectrum sunscreen once your doctor says it is fine to apply.
7. A cool compress wrapped in a clean cloth may help with swelling and tenderness.

When to Contact Your Doctor

Get in touch with the clinic or seek medical advice if you notice:

• Bumps that are getting larger, harder or more painful after the first couple of days
• Lumps still clearly visible after two weeks
• Spreading redness, heat, pus or fever
• Itching, hives or swelling away from the treated area
• Any difficulty breathing or swelling of the lips or tongue, which needs emergency care

If you are travelling, ask before you leave how to reach the clinic and what to do if a problem appears after you return home. Keep a note of the product used so another doctor can understand what was injected.

Reducing the Chance of Noticeable Bumps

Bumps cannot be avoided completely with standard technique, but you can talk with your doctor about options. Some practitioners use injector devices or cannulas for certain areas, adjust the depth or amount per point, or choose a different version of the product. These choices can involve trade-offs, so it is worth discussing whether your priority is minimal downtime or a particular technique.

Frequently asked questions

Do the bumps mean the treatment is working?

They show that product was placed superficially, as intended, but the size of the bumps does not predict how good your final result will be.

Can I cover the bumps with makeup?

Most doctors suggest waiting at least until the next day so the needle points can close. Check the advice you were given.

Will the bumps be smaller at later sessions?

Some people find later sessions easier, but this varies. Technique and skin condition on the day often matter more.

Is a bruise a sign of a problem?

Usually not. Small bruises are common with any facial injection and fade over a week or so.

Speak With a Dermatologist

Bumps after Rejuran are normal and short-lived for most people, but your skin, health and schedule are unique. A qualified dermatologist can explain what to expect in your case, adjust technique where appropriate, and assess any reaction that does not settle as expected.