Definition & Overview

Keloid injection, also called intralesional injection, is one of the methods currently being used for the treatment of keloid scars. Although there are other available options, such as the use of laser or surgery, intralesional injection is considered the safest and less painful means of treating the said skin condition.

Keloid is a type of overgrown scar tissue that typically develops around a wound or lesion several months after healing. There is no definitive cause for this condition, though it is known that some individuals are more predisposed to it than others. This type of skin aberration is characterised by the presence of excessive hyalinised collagen bundles and appears as dome-shaped raised tissues, which are considered aesthetically unattractive. Most look shiny and are reddish to dark brown in colour and can also be itchy or tender to touch. Some patients even report a burning sensation in the growth site. These skin growths typically occur, though not restricted, in the shoulder, breastbone, cheek, and even the earlobe.

There are several types of substances that can be injected into the body for the treatment of keloid scars. The most common is corticosteroid, which is very popular in treating pathological scars due to its ability to suppress vascular endothelial growth. Other substances that are used due to their ability to suppress collagen production are:

  • 5-fluorouracil, which is also an anti-neoplastic agent
  • Bleomycin, which also induces fibroblast cell death
  • Interferon, which is also known to be antiviral and antifibrotic
  • Verapamil

    Who Should Undergo and Expected Results

Keloid scars are more common among people with darker complexion, like those belonging to the African-American, Hispanic, and Asian races as well as those who are experiencing an increase in hormonal levels, such as those entering puberty.

These people are the best candidates for the keloid injection treatment. They can take advantage of the procedure particularly if (1) they are experiencing the cosmetic and psychological impacts of keloids, (2) their qualify of life is severely affected due to the itching and pain associated with the condition, and (3) if the keloid has reduced the function of the affected body part.

Keloid injection is also offered to those whose abnormal growth results from acne, vaccinations, laceration, burns and biopsy.

This procedure typically requires several sessions to achieve the desired outcome, with the injection given once every month or at longer or shorter intervals, depending on the size of the lesion and dosage given. Most patients report high satisfaction, with the keloid flattened and significantly reduced in size at the end of the treatment period, alleviating the emotional distress experienced by patients. Although the treatment site cannot be totally restored to its previous state prior to the development of keloid scars, most patients will no longer suffer from its unsightly appearance.

How is the Procedure Performed?

Keloid injection is a simple procedure done in an outpatient setting.

The dermatologist will start by determining the appropriate type of keloid injection to use as well as the correct dosage to administer based on the size of the keloid scar, its location, and the patient’s age. The treatment substance is injected at mid-dermis, just slightly below the skin. During subsequent visits, the dermatologist may adjust the dosage, depending on the tissue’s response to the treatment and overall appearance of the keloid.

There are some substances, like the bleomycin, which are injected using the multi-puncture technique, similar to that of applying tattoo dye.

Possible Risks and Complications

  • Slight pain at the injection site following each session
  • Swelling and hyperpigmentation on the injection site
  • Steroid acne growth following the administration of corticosteroids
  • The development of linear hypopigmentation, characterised by streaky patches of white skin occurring in the arms and legs. This complication could resolve itself over time or could also be permanent.
  • Wound ulceration and erythema
  • Scratch dermatitis and fibrosis; these are possible reactions to the injected substances
  • Alopecia, or losing patches of hair
  • Flu-like symptoms like fever and headache for those administered with interferon

Though keloid injection is considered highly effective in reducing keloid growth, there is still the possibility of recurrence of this dermal condition. In some cases, patients may need to undergo another round of treatment or may consider trying other types of substance or treatment methods (such as surgery) if necessary.


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  • Al Aradi IK, Alawadhi SA, Alkhawaja FA. Earlobe keloids: a pilot study of the efficacy of keloidectomy with core fillet flap and adjuvant intralesional corticosteroids. Dermatol Surg. 2013 Oct. 39(10):1514-9.

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