Intralesional Steroid Injection

Intralesional steroid injection involves a corticosteroid, such as triamcinolone acetonide or betamethasone or depo-medrol suspension, which is injected directly into a lesion on or immediately below the skin.

Intralesional administration of corticosteroids is used to treat a dermal inflammatory process directly. 

In contrast to topical steroids, intralesional steroids:

• bypass the barrier of a thickened stratum corneum
• reduce the chance of epidermal atrophy (surface skin thinning)
• deliver higher concentrations of the steroid to lesion minimizing adverse effect to other body parts
• Reduce systemic effects of the drug. 

Administration of intralesional steroid

Intralesional triamcinolone is injected directly into the skin lesion using a fine needle after cleaning the site of injection with alcohol or antiseptic solution. The injection should be intradermal, not subcutaneous, to avoid causing a dent in the skin.

Intralesional injection is a typical intradermal injection in which the injection needle has to be in slanting position between 10-15 degrees to the skin site surface. The diagram below may explain that.

The initial dose per injection site will vary depending on the lesion being treated. Generally, 0.1–0.2 mL is injected per square cm of involved skin. The total dose should not normally exceed 1 or 2 mL per dose. It can be repeated every 4 to 8 weeks.

The corticosteroid can be full strength (eg triamcinolone 10 mg/mL or 40 mg/mL) or diluted with normal saline or local anaesthetic. Typical regimes for triamcinolone intralesional injections include:

40 mg/mL for a thick keloid scar

10 mg/mL for a moderate thickness hypertrophic scar

10 mg/ml into discoid lupus erythematosus or granuloma annulare

5 mg/ml into skin of normal thickness associated with alopecia areata.

The injections may be repeated monthly for a few months while the lesions are active.

Uses of Triamcinolone injection

Kenalog (triamcinolone) is used to treat inflammation caused by allergic reactions, eczema, and psoriasis. Triamcinolone (injection) is used to treat inflammation associated with a variety of conditions, including allergies, diseases of the skin, endocrine disorders, inflammation of the intestines, blood disorders, kidney diseases, and diseases and inflammation of the eye. Triamcinolone is also sometimes used intramuscularly as an alternative to oral corticosteroids, for example for seasonal hay fever, or to treat a chronic skin disorder such as atopic dermatitis or lichen planus.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Contraindications to intralesional steroid

Intralesional steroids should not be injected at the site of active skin infection e.g., impetigo (school sores) or herpes simplex (cold sores). Triamcinolone should be avoided in the following cases:

• Active or latent tuberculosis 
• systemic fungal infections
• Intestinal infection caused by the roundworm Strongyloides
• hypothyroidism
• Diabetes Mellitus
• Insufficiency of the Hypothalamus and Pituitary Gland
• Hypercholestrolaemia
• Hypokalaemia
• Immunocompromised patient
• Wide-Angle Glaucoma or Cataracts
• Non controlled hypertension
• Chronic Heart Failure
• Ulcer from Stomach hyperacidity
• Osteoporosis or decreased Calcification or Density of Bone
• Visible Water Retention or oedema or Cushing Syndrome
• Inherited Arginosuccinate Lyase Deficiency
• Inherited Carbamyl Phosphate Synthetase Deficiency
• Infection caused by the Varicella Zoster Virus or Measles or Chicken Pox or Monkey Pox

Triamcinolone should be avoided in patient who has hypersensitivity to triamcinolone.

Side effects arising at the site of intralesional steroid injection

They include:

Pain, bleeding, bruising

Infection

Contact allergic dermatitis due to the preservative, benzyl alcohol

Impaired wound healing

Sterile abscess, sometimes requiring surgical drainage

Cutaneous and subcutaneous lipoatrophy (most common) appearing as skin indentations or dimples around the injection sites a few weeks after treatment; these may be permanent.

White marks (leukoderma) or brown marks (postinflammatory pigmentation) at the site of injection or spreading from the site of injection – these may resolve or persist long term.

Telangiectasia, or small dilated blood vessels at the site of injection. These can be treated if necessary by laser or intense pulsed light (IPL).

Increased hair growth at the site of injection (localised hypertrichosis) – this resolves eventually.

Localised or distant steroid acne: steroids increase growth hormone, leading to increased sebum (oil) production by the sebaceous glands. Steroid acne generally improves once the steroid has been stopped.

Systemic side effects of triamcinolone injections

Allergic reactions are very rare, and dose independent but may include local or generalised urticaria (wheal and flare), and in more severe cases, anaphylaxis (angioedema, swollen face/tongue, respiratory distress, hypotension/shock).

Other systemic side-effects are not likely to follow intralesional injection of localised skin disease because the dose used is very small.

However, the following potentially serious conditions have been reported from intramuscular injection of large doses of triamcinolone acetonide.

• Heart: congestive heart failure in susceptible patients, fluid retention, hypertension, cardiac arrhythmias.
• Hormones: decreased glucose tolerance, Cushing syndrome, hirsutism, hypertrichosis, manifestations of latent diabetes mellitus, menstrual irregularities, adrenocortical and pituitary unresponsiveness, suppression of growth in children.
• Musculoskeletal: aseptic necrosis of hip or shoulder bones, calcinosis, osteoporosis and pathological fractures, muscle weakness, tendon rupture.
• Neurologic/psychiatric: convulsions, depression, euphoria, swelling of the brain, insomnia, mood swings.
• Eyes: glaucoma, cataracts, rare instances of blindness associated with periocular injections.

For more information about triamcinolone or the right steroid for your condition, contact your pharmacist or doctor.