How common is allergy with aesthetic injections?
Serious allergic reactions are rare. More often seen are temporary effects of the injection itself, such as redness, mild swelling and itching, which are usually not true allergy.
Not every redness after an injection is an allergy. A local reaction to the needle, the tissue's usual response to the product and mild swelling are common and usually settle within days. A true allergic reaction is an exaggerated immune response to a component of the product or an accompanying substance and is much less common.
Being rare does not mean the risk is zero. This is why a detailed health history and treatment in a setting prepared for a possible reaction matter.
What are the signs of an allergic reaction?
Mild signs are redness, itching and local swelling. More serious signs are widespread redness or hives, swelling of the face, lips or tongue, difficulty breathing or swallowing, dizziness and palpitations.
Mild reactions usually stay at the treated area and appear within hours. In that case, tell the treating doctor without interfering with the area; the doctor will assess it. It is advised not to start any medication on your own.
Widespread hives, marked facial swelling, a feeling of swelling in the lips, tongue or throat, shortness of breath, wheezing, difficulty swallowing, dizziness and a feeling of fainting may signal a serious reaction. These are emergencies: call 112 without delay. Other important warnings are on our warning signs page.
Is an allergy test done before treatment?
A routine allergy test is not done for every treatment. If there is a known allergy history, the doctor reviews the product's composition, may postpone, or may choose a different product.
Which test is suitable depends on the product and the personal history, so a general rule would not be right. At the consultation, mention past reactions to drugs, local anaesthetics, latex or foods, reactions after earlier aesthetic treatments and any allergic conditions.
Some fillers contain lidocaine; a known lidocaine allergy should be mentioned beforehand. Botulinum toxin is a protein, and treatment is not advised in people known to be sensitive to a component. All of this needs a doctor's assessment and should be read together with our page on when treatments are not suitable.
Who needs extra care regarding allergy?
People with a history of drug, lidocaine or product-component allergy or severe allergy, those with autoimmune disease and those who had a reaction after a previous injection are assessed more carefully.
A history of severe allergy, drug allergies and conditions such as asthma should be shared before treatment. If you had prolonged swelling, firmness or redness after any earlier filler or Botox, this guides the doctor's choice of product and technique.
Pregnancy, breastfeeding and some chronic conditions also affect the assessment, and these are covered on separate pages. Listing all your medicines and supplements makes it easier to spot possible interactions.
What should you do if you suspect an allergy?
If there are emergency signs, call 112. For non-urgent redness, itching or swelling that worries you, contact the treating doctor and avoid using medicines or creams on your own.
The doctor assesses whether the reaction is an allergy, a usual healing sign or something else such as infection. Photographing the area and noting when it started and how it changed speeds up assessment.
Firmness or swelling that develops weeks or months later may be a delayed reaction and also needs a doctor's assessment. Choice of treatment and any medicines are the doctor's responsibility and should not be replaced by methods learned online.
Frequently asked questions
What happens if I am allergic to Botox?
Botox allergy is rare; signs range from redness and itching to difficulty breathing. For serious signs call 112, and for mild reactions contact the treating doctor.
Can I have filler if I am allergic to lidocaine?
The answer depends on the product and your history. Telling the doctor before treatment lets a lidocaine-free option be considered.
Is itching after filler an allergy?
Mild, short-lived itching is often part of normal healing. Widespread or worsening itching, or itching with swelling, should be reported to the doctor.
Do I need an allergy test?
A routine test is not needed for every treatment. If you have a known allergy, sharing it at the consultation helps the doctor decide on precautions.
Could swelling weeks later be an allergy?
Delayed reactions can occur, and not every swelling is an allergy. A doctor's assessment is needed to tell it apart from causes such as infection.
Sources (4)
- U.S. FDA: Dermal Fillers (Soft Tissue Fillers)
- EMA: Nuceiva (botulinum toxin type A): Annex I, Summary of Product Characteristics (2024)
- American Society for Dermatologic Surgery: Preventing and Treating Adverse Events of Injectable Fillers: Evidence-Based Recommendations From the American Society for Dermatologic Surgery Multidisciplinary Task Force (2021)
- U.S. FDA / Allergan: BOTOX Cosmetic (onabotulinumtoxinA) for injection: Highlights of Prescribing Information (2024)
This content is for general information and does not replace a personal medical assessment.