Filler Complications: Swelling, Nodules, the Tyndall Effect, Late Reactions and Dissolving Filler

Why do filler complications occur?

A filler is a gel-like product injected into or under the skin. Complications generally arise from three sources: the person’s individual characteristics (skin type, immune response, medicines they take), the characteristics of the product (whether it is hyaluronic acid, how dense it is) and the injection technique (amount, depth, area).

Expert consensus reports state that most adverse effects of hyaluronic acid fillers are mild and temporary, and that serious events are rare. Even so, filler is not risk-free. For the basics of the treatment, see our article “Hyaluronic Acid Filler”.

Early phase: are swelling, bruising and palpable irregularities normal?

In the first days after the treatment, the following are common and usually pass on their own:

• Swelling: may be marked, especially in the lips and under the eyes; it increases in the first days and then goes down.
• Bruising: small, well-defined bruises at the injection points; they fade over time, turning yellow-green.
• Tenderness and mild redness.
• Small palpable irregularities or bumps: these usually decrease as the swelling goes down.

For how swelling and bruising develop and how to reduce them, see our article “Bruising and Swelling”.

Overcorrection, that is, the area looking fuller than intended, is also an early-phase problem. Because the swelling in the first days can be misleading, assessing the final result usually requires waiting a few weeks. If there is still excess fullness or marked asymmetry after this time, your physician will discuss the options with you.

What is the Tyndall effect? Why does a bluish tint appear under the eyes?

The Tyndall effect is a bluish or grey-blue appearance of the area caused by light scattering in the gel when a hyaluronic acid filler has been placed too superficially in the skin. It is seen particularly under the eyes, where the skin is thin. Unlike a bruise, the colour does not turn yellow and fade over time, and it can last for weeks.

The Tyndall effect is not an emergency, but it can take a long time to go away on its own. Your physician will usually suggest dissolving the hyaluronic acid in the area with the enzyme hyaluronidase. A bluish-purplish colour that starts suddenly, is painful and spreads like a net, however, is not the Tyndall effect; in that case, see the emergency warning below.

Vascular occlusion: the most important emergency complication

Filler blocking a blood vessel is a rare but serious complication and requires intervention within minutes to hours. We have described the warning signs and what you should do in detail in our article “After Fillers: When Is It an Emergency?”.

How can infection and abscess after filler be recognised?

Infection can develop when germs enter through the tiny channel the needle makes in the skin. Symptoms usually start a few days after the treatment: redness, warmth, increasing pain and swelling, sometimes discharge and fever. An abscess is a collection of pus in a cavity under the skin and feels like a soft, painful swelling when touched.

If you notice signs of infection, see a physician without delay. The physician decides on the treatment; if there is an abscess, it may need to be drained. Do not start antibiotics on your own. For details, see our article “Infection after Aesthetic Treatments”. After treatments around the lips, people with a history of cold sores may also have a cold sore flare-up; if you have a history of cold sores, mention it before the treatment.

Delayed nodules and biofilm: why does swelling appear weeks or months later?

A nodule is a firm or soft lump that can be felt under the skin. The causes differ, and the treatment varies accordingly:

• Product accumulation: forms when the filler collects in one spot; it is usually painless and noticed early.
• Delayed inflammatory reaction: weeks or months later, swelling, redness and tenderness may appear in the area. It sometimes occurs after a trigger such as a flu-like illness, a vaccination or dental treatment.
• Biofilm: bacteria settling on the surface of the filler by forming a thin layer. It can be difficult to detect with ordinary tests and can lead to recurring swelling.

Only the physician who examines you can assess the cause of a nodule; imaging methods such as ultrasound may sometimes also be used. Depending on the situation, the physician may consider monitoring, dissolving the filler, medication or a combination of these. Scientific knowledge about the causes and the most suitable treatment of delayed nodules is still developing.

Granuloma and filler migration

A granuloma is inflammatory tissue that the body forms around a product it perceives as a foreign substance. It is rare; it can appear months or even years later as firm, sometimes growing lumps. Diagnosis and treatment require specialist assessment.

Migration is when the filler moves from where it was injected into neighbouring areas. Examples include lip filler spreading above the lip border or under-eye filler forming a noticeable bulge. With hyaluronic acid fillers, the physician may suggest dissolving the product that has moved.

How is filler dissolved? What you need to know about hyaluronidase

Hyaluronidase is an enzyme that breaks down hyaluronic acid. When injected by a physician into the filler area, it can largely dissolve hyaluronic acid filler. It can be used in emergencies such as vascular occlusion, for the Tyndall effect, to remove product that has moved or is excessive, and for some nodules.

• It only works on hyaluronic acid fillers. It does not dissolve fillers made of other substances.
• It is a prescription medicine and a medical procedure; it should be administered by a physician after an examination.
• An allergic reaction is rare but possible. The risk may be higher in people who are allergic to bee or wasp stings; so be sure to mention your history of allergies.
• In non-urgent situations, the physician may sometimes prefer to do a small skin test first. In emergencies such as vascular occlusion, however, the physician decides by also weighing up the risk of waiting.
• After dissolving, there may be temporary swelling and tenderness in the area; sometimes more than one session may be needed.
• If new filler is to be considered after the result has been assessed, your physician will decide on the timing.

Why is treatment more difficult with fillers that are not hyaluronic acid?

There are also fillers on the market that do not dissolve in the body or stay for a very long time. These products cannot be dissolved with hyaluronidase. Problems such as nodules or granulomas related to them can appear even years later and are more difficult to treat; medication is not always sufficient and surgery may sometimes be needed. Surgical removal is not always possible either and carries its own risks.

This is why it is important to know which product was used on you. Ask for the product type and the date of the treatment in writing; if you see another physician years later, this information makes treatment easier.

Which complication appears when?

The time when a complication appears gives an important clue to its cause. The table below is a general framework; not every problem always fits this time window.

What are the treatment options? What can your physician do?

The treatment of filler complications depends on the type of problem, whether the product is hyaluronic acid and when the symptoms started. Your physician will first examine you; if necessary, they may request imaging or laboratory tests. They may then recommend one or more of the following approaches:

• Waiting and monitoring: most early swelling and irregularities decrease on their own.
• Dissolving the filler: with the enzyme hyaluronidase, for hyaluronic acid fillers.
• Medication: when infection or an inflammatory reaction is suspected, medicines the physician considers appropriate. These treatments require a prescription and follow-up.
• Interventional procedures: draining an abscess or, in some cases, surgically removing the product.
• Referral: if necessary, to the relevant specialties such as dermatology, plastic surgery, ophthalmology or infectious diseases.

If you have a complication, the physician who performed the treatment is your first point of contact. If you cannot reach them or you do not feel reassured, you also have the right to get an opinion from another physician; in that case, take the product and treatment information with you.

Normal, consult your physician, or emergency?

What can you do at home, and what should you avoid?

• Follow the aftercare instructions your physician gave you; do not press on the area.
• Note any change with the date and a photo; keep the information on the product type and the date of the treatment with you.
• Whenever you are unsure, call the physician who performed the treatment.

Do not do the following:

• Unless your physician specifically recommends it, do not massage or squeeze a nodule or swelling.
• Do not apply heat to the area without consulting a physician.
• Do not use antibiotics, steroid creams or other medicines on your own.
• Do not buy filler-dissolving products online or inject yourself.
• Do not have a new procedure on the same area somewhere else to fix the problem.

How can filler complications be prevented?

To reduce the risk:

• Have the treatment done by a physician who knows facial anatomy and is experienced in managing complications, in a licensed healthcare facility.
• Ask whether hyaluronidase enzyme and emergency facilities are available where the treatment is done.
• Tell your physician about cold sores, allergies, autoimmune diseases, the medicines you take and any previous filler treatments.
• If you have an active skin infection, spots or a cold sore, discuss postponing the treatment with your physician.
• If you are planning a vaccination or dental treatment soon, ask your physician about the timing.
• Stay away from products of unknown origin and from treatments outside healthcare facilities.