Delayed Filler Complications: Lessons From a Case Series

A 2025 report from a dermatology practice in Lebanon described three women who developed lumps, swelling or infection weeks to months after hyaluronic acid filler. Each problem had a different cause and needed a different treatment, and the authors stress that working out the cause first, often with ultrasound, is what made treatment succeed.

Why this was studied

Most people who have hyaluronic acid filler notice only short-lived swelling or bruising. A small number, though, develop problems that appear later: firm bumps, puffiness that comes and goes, or a red, painful area. These are usually called delayed complications, and they are generally defined as starting more than two weeks after treatment.

Delayed reactions are uncommon, but they can be confusing. Similar-looking lumps can come from an immune reaction, a buildup of filler, a granuloma (a cluster of immune cells walling off material the body sees as foreign) or a low-grade infection. Because the right treatment for one can be the wrong treatment for another, doctors benefit from seeing how real cases were worked through. For a general overview, see our article on delayed swelling and lumps after filler.

What the researchers did

The two authors described three patients they had treated, aged 38 to 60, including the timing of their symptoms, the tests used and how each responded. This is a case series, which means there was no comparison group and no attempt to measure how often these reactions happen.

What they found

The three cases illustrate three different patterns:

• A granuloma. One woman developed firm nodules around the mouth and cheeks about three months after treatment. A small skin biopsy confirmed a foreign-body granuloma. A short course of oral steroids helped little, an enzyme injection shrank the nodules somewhat, and steroid injections directly into the nodules cleared them.
• Recurring swelling from filler in unexpected places. A second woman had swelling that kept coming back for well over a year. Earlier courses of antibiotics, steroids and "blind" enzyme injections only helped briefly. Imaging showed filler sitting in deeper areas than expected. When the enzyme hyaluronidase was injected under ultrasound guidance, directly into the deposits, the swelling settled within about a week and did not return.
• Infection. A third woman, treated by an unlicensed practitioner, developed painful lip swelling with abscesses about two weeks after injection. She needed antibiotics and drainage first. Only after the infection was under control was hyaluronidase used, and the problem resolved.

How strong is this evidence?

A case series of three patients is a low level of evidence. It cannot tell us how common these complications are, which treatment works best, or whether the same approach would help someone else. The patients had different products, areas and histories, and some had other possible contributing factors. What a report like this does well is show clinical reasoning in real situations and highlight lessons worth testing in larger studies.

Lessons worth noting

Several practical points stand out from the authors' discussion:

• Find the cause before treating. Infection, inflammation and granulomas are managed differently. The authors advise ruling out infection before using hyaluronidase, and taking a sample for culture from any pus-filled area.
• Imaging can help. Ultrasound showed where filler actually was, separated abscesses from filler deposits and guided injections to the right spot. In the second case, the same enzyme that failed when injected without imaging worked once it was targeted.
• Granulomas behave differently. The authors note these usually respond best to steroid injections into the lump, with other options reserved for stubborn cases.
• Prevention matters. They emphasise thorough makeup removal, careful skin antisepsis, screening patients beforehand, treatment by licensed and trained injectors, and keeping makeup and tap water off the treated skin for at least eight hours afterward.

What it means for you

If you have had filler, it is worth knowing that a late reaction is possible, even though most people never experience one. Contact the clinic that treated you if you notice:

• New lumps or firmness weeks or months after treatment
• Swelling that comes and goes, especially after an illness or dental work
• Redness, warmth, increasing pain, or any discharge
• Fever or feeling unwell along with facial swelling

Avoid trying to treat these at home or with leftover antibiotics. The cases in this report show that the right treatment depends on the cause, and repeated trial-and-error courses may delay the right care. Signs of spreading infection, or any change in vision, need urgent medical attention.

It also helps to keep a simple record of every filler treatment you have had, including the date, the areas treated and the product name. If a late reaction appears years later, or you see a different practitioner, that information can save time and point toward the right diagnosis sooner.

Questions to ask at your consultation

• What should I watch for in the weeks and months after filler?
• Who do I contact if a late reaction happens, and how quickly can I be seen?
• Is hyaluronidase available, and when would it be appropriate?
• Will you keep a record of the exact product and areas treated in case I need it later?

Frequently asked questions

Can a lump appear months after filler even if everything was fine at first?

Yes, although it is uncommon. Delayed reactions can start weeks, months or occasionally longer after treatment, which is why keeping a record of your treatment details is useful.

Does dissolving the filler always fix a late lump?

Not always. Hyaluronidase often helps when filler itself is the problem, but infections need treating first, and granulomas may need other approaches. A medical assessment guides the choice; our article on dissolving filler with hyaluronidase explains the enzyme in more detail.

If you have questions about filler safety or a reaction you have noticed, HealthPark Medical Aesthetics can talk it through with you at a consultation and, where needed, coordinate with your family doctor.

Source

Saad Y, Tannous Z. Management of Delayed Complications of Hyaluronic Acid Fillers: Case Series From the Middle East. Journal of Cosmetic Dermatology, 2025. Read the study