Raised acne scars—particularly hypertrophic and keloid types—are more than a cosmetic issue. In Singapore’s tropical climate and ethnically diverse population, these scars can be both physically uncomfortable and emotionally distressing, especially for skin types prone to pigmentation. Among the available treatment options, steroid injections are one of the methods sometimes recommended to manage raised scar tissue. This guide explains how they work, who may benefit, what to expect, and how they fit into the broader landscape of acne scar treatment in Singapore.
What Are Steroid Injections?
Steroid injections are a form of intralesional therapy, where a corticosteroid drug is injected directly into scar tissue. They are most often used for:
- Hypertrophic scars – raised but confined to the original acne lesion
- Keloid scars – raised, extending beyond the original lesion and often recurring
Steroid injections are a clinically established method for managing raised scars, with their use supported in dermatology and aesthetic medicine literature for more than four decades.
The main treatment goals are to:
- Relieve symptoms such as itch, tightness, or pain
- Flatten the scar by reducing excessive scar tissue formation
The most commonly used medication is triamcinolone acetonide, prepared in concentrations between 2.5 mg/mL and 40 mg/mL depending on scar thickness, skin sensitivity, and treatment depth. A very fine needle (30–32G) ensures precise delivery. In some cases, the injection may be combined with a small amount of anaesthetic for comfort.
Steroid injections are usually chosen when topical creams are ineffective or when patients prefer a non-surgical approach.
How Steroid Injections Work on Raised Scars
Steroid injections act directly within scar tissue to alter the abnormal wound-healing process. Instead of describing the purpose in general terms, this section explains the cellular mechanisms that bring about change.
Mechanism of Action
When injected into raised scars, corticosteroids influence both scar-forming cells and blood vessels:
- Suppress inflammatory signals such as interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF-α) → reduces the biochemical “alarm signals” that keep scars active
- Reduce fibroblast proliferation → limits production of collagen and glycosaminoglycans, which are the structural components of excess scar tissue
- Constrict small blood vessels (vasoconstriction) → decreases redness and vascularity
- Net effect → the scar gradually becomes softer, flatter, and less symptomatic
Effect by Scar Type
| Scar Type | Typical Response | Clinical Notes |
|---|---|---|
| Hypertrophic scars | Consistent flattening and softening | Improvements often seen within 2–4 sessions |
| Keloid scars | Variable improvement; higher recurrence | Often require ongoing or combination treatments (e.g., 5-FU, cryotherapy, PDL laser) |
Hypertrophic scars generally respond more predictably, while keloids often need a longer-term, multi-modal strategy.
Who Is Suitable for Steroid Injections?
Not all acne scars require or benefit from steroid injections. Suitability depends on the type of scar, its age, your medical history, and how much the scar affects your comfort or confidence.
When Steroid Injections May Be Considered
Steroid injections are often recommended if your scars are:
- Raised and active – firm, itchy, or expanding hypertrophic or keloid scars.
- Relatively new – scars that formed within the past 1–2 years and are still changing.
- Symptomatic – scars that cause pain, tenderness, or a pulling sensation.
- Distressing – scars that affect your confidence or daily comfort.
When Steroid Injections May Not Be Suitable
They may not be advised if you have:
- Flat or depressed scars – such as boxcar, ice-pick, or rolling scars (these need other treatments like subcision or laser).
- Active skin infection – injection may worsen infection.
- Delayed wound healing – common with uncontrolled diabetes or circulation problems.
- Corticosteroid sensitivity or allergy – though rare, this prevents use.
- Pregnancy or breastfeeding – usually avoided unless essential.
Timing and Skin Profile Considerations
- Scar age – younger scars (<1 year) respond better; older scars may require more sessions or combined therapies.
Skin tone – medium to darker skin types (common in Singapore) carry higher pigment risk; doctors use adjusted concentrations and stress sun protection. - Scar location – high-tension areas (chest, shoulders, jawline) are more prone to recurrence.
Quick Reference Table
| Factor | More Suitable | Not Suitable / Caution |
|---|---|---|
| Scar Type | Hypertrophic, keloid | Atrophic (boxcar, ice-pick, rolling) |
| Scar Age | < 2 years, active or expanding | Mature, stable scars with no symptoms |
| Skin Type | All (with adjusted dosing/technique) | Darker tones without strict sun protection |
| Medical History | No active infection, stable health | Steroid allergy, uncontrolled diabetes, impaired healing |
Patient Profile
You are more likely to benefit from steroid injections if you are:
- Committed to completing multiple sessions spaced 3–6 weeks apart.
- Able to follow aftercare instructions such as sun protection and silicone gel use.
- Aware that improvement is gradual, not immediate, and that keloids in particular may need ongoing treatment.
Steroid Injection Procedure: What to Expect
Steroid injections for raised acne scars are performed in a clinic setting. The procedure is quick, involves minimal downtime, and is tailored to the type and size of your scar.
1. Consultation and Assessment
Before treatment, your doctor will:
- Evaluate your scars – confirm whether they are hypertrophic or keloid in nature
- Review your medical history – check for conditions such as diabetes, delayed healing, or past steroid use
- Assess your skin tone – adjust dosing to reduce the risk of pigment changes, particularly in medium to darker skin types common in Singapore
- Discuss prior treatments – such as silicone gels, lasers, or other scar therapies
- Explain expectations – outline likely benefits, limitations, and the number of sessions you may need
2. Injection Procedure
The actual procedure typically involves:
- Cleansing and disinfecting the skin around the scar
- Applying a topical anaesthetic (optional) to reduce discomfort
- Using a fine needle (30–32G) to deliver a diluted steroid solution directly into the scar tissue
- Multiple injection points for larger scars to ensure even distribution
- Use of lidocaine (local anaesthetic) in some cases to reduce pain during injection
The procedure usually takes just a few minutes per scar.
3. Treatment Plan and Frequency
The number of sessions and the interval between treatments depend on scar type and response:
| Scar Type | Typical Sessions | Frequency Between Sessions |
|---|---|---|
| Mild hypertrophic | 2–3 | Every 4–6 weeks |
| Moderate hypertrophic | 3–5 | Every 3–5 weeks |
| Small to medium keloid | 4–6+ | Every 3–4 weeks |
Most patients begin to notice softening and flattening after 2–3 sessions. Keloid scars may require ongoing maintenance sessions to reduce recurrence.
Key Point: The procedure is straightforward, but success depends on tailoring the dose, depth, and number of sessions to your scar type and skin profile. A stepwise plan allows your doctor to monitor progress and adjust treatment as needed.
Benefits and Limitations of Steroid Injections for Raised Acne Scars
Steroid injections are a well-established treatment for raised acne scars. They can reduce symptoms and improve scar appearance, but they also have clear limitations that patients should understand before starting treatment.
Benefits
Steroid injections may help by:
- Relieving symptoms such as itch, tightness, or pain.
- Flattening raised scars by softening scar tissue and reducing height.
- Improving colour by reducing redness through blood vessel constriction.
- Offering convenience since the procedure is quick, clinic-based, and requires little downtime.
Limitations
They may also present challenges:
- Not suitable for all scars – they work on hypertrophic and some keloid scars, but not on atrophic scars like boxcar, ice-pick, or rolling types.
- Recurrence risk – especially in keloid scars.
- Plateau effect – improvement may slow after a few sessions.
- Cosmetic limits – scars flatten but the skin’s original smooth texture cannot be fully restored.
Summary Table
| Aspect | Benefit | Limitation |
|---|---|---|
| Symptom relief | Itch, pain, and tightness often improve | Relief may be temporary if the scar is aggressive |
| Scar flattening | Effective for hypertrophic scars | Less predictable for large or old keloids |
| Colour changes | Redness often decreases | Pigment changes may occur, especially in darker skin |
| Durability | Long-lasting with proper aftercare | Recurrence possible, particularly for keloids |
Risks and Possible Side Effects
Steroid injections for raised acne scars are generally safe when carried out by trained professionals. However, like any medical procedure, they may cause side effects. These are usually local and temporary, but some risks are more likely in certain patients or skin types.
Common Local Effects
- Skin thinning (atrophy) – small indentations or depressions when steroid spreads to surrounding tissue
- Hypopigmentation – lightening of the skin around the injection site, especially in medium to darker skin tones
- Telangiectasia – appearance of fine, visible blood vessels on the treated area
- Redness or irritation – mild inflammation or blanching that usually settles within hours
Less Common Effects
- Steroid-induced acne or folliculitis – acne-like bumps forming near injection sites
- Delayed healing – more likely in patients with uncontrolled diabetes or poor circulation
- Allergic reactions – rare, usually linked to preservatives in the steroid formulation
- Systemic absorption – very uncommon at acne scar doses, though possible in repeated high-volume treatments
Risk Factors
- Skin type – medium to darker tones (Fitzpatrick III–V) have higher pigment change risk
- Scar location – high-tension areas (chest, shoulders, jawline) more prone to recurrence
- Treatment history – frequent or high-dose injections increase chance of skin thinning or pigment change
In Singapore, steroid injections for acne scars are performed within the framework of Ministry of Health (MOH) regulations, which ensure that aesthetic treatments are delivered with patient safety and ethical practice in mind.
Aftercare and Recovery
Steroid injections usually involve minimal downtime, but good aftercare reduces discomfort, supports healing, and lowers the chance of side effects. In Singapore’s hot, humid climate, aftercare is particularly important because heat, sweat, and UV exposure can worsen irritation and pigmentation.
Immediately After Treatment (First 24 Hours)
- Mild redness, swelling, or tenderness is common and usually resolves within a day
- Avoid touching or pressing on the treated area
- Do not apply makeup, sunscreen, or active skincare (e.g., acids, retinoids) for 12–24 hours
- Apply a clean cold compress gently if there is discomfort
First 48 Hours
- Avoid strenuous exercise or heavy sweating
- Do not use exfoliants or retinoids while the skin is sensitive
- Cleanse with a mild, pH-balanced cleanser
Ongoing Home Care (Weeks Following Treatment)
- Sun protection → daily SPF 50+ sunscreen reduces risk of pigmentation
- Moisturiser → fragrance-free, non-comedogenic products support hydration and skin repair
- Gentle handling → avoid friction from straps, towels, or clothing
- Silicone gels or sheets → start 24–48 hours after treatment; use twice daily for 8–12 weeks
- Spacing → follow doctor’s schedule (3–6 weeks between sessions) to prevent overexposure
Aftercare Summary Table
| Risk/Concern | Prevention & Management |
|---|---|
| Skin thinning | Adequate spacing, correct injection depth |
| Hypopigmentation | Daily sun protection, cautious dosing for darker skin |
| Redness/Irritation | Usually self-resolves; use cold compress |
| Steroid-induced acne | Maintain hygiene; topical treatment if persistent |
| Delayed healing | Monitor diabetic patients, avoid unnecessary trauma |
Alternatives and Combination Treatments
Steroid injections are effective for many raised acne scars, but they are not the only option. In some cases, combining treatments leads to better outcomes, particularly for resistant keloids. The choice depends on scar type, age, and location.
Steroid Plus 5-Fluorouracil (5-FU)
5-FU is a chemotherapy agent that inhibits fibroblast activity. When combined with steroids, it enhances scar flattening and reduces the steroid dose required.
- Best suited for: thick or recurrent keloids, especially on the jawline, chest, or shoulders.
- Treatment approach: multiple sessions delivered in combination by specialists.
Steroid Plus Cryotherapy
Cryotherapy uses liquid nitrogen to freeze and shrink scar tissue. Freezing softens the scar, and the steroid reduces the chance of rebound inflammation.
- Best suited for: firm, nodular keloids on the back and shoulders.
- Cautions: may cause blistering or pigmentation changes, so technique and clinical experience are critical.
Steroid Plus Pulsed Dye Laser (PDL)
PDL targets blood vessels in the scar, reducing redness and vascularity. When combined with steroids, it improves flattening while reducing colour and discomfort.
- Best suited for: hypertrophic scars with persistent redness or early-stage keloids.
- Treatment plan: usually requires several laser sessions alongside injections.
Other Adjunct Options
- Silicone gels or sheets → maintain pressure, hydration, and long-term flattening.
- Surgical excision plus postoperative steroid injections → reserved for large or resistant keloids, usually combined with other treatments to reduce recurrence.
- Energy-based treatments (microneedling, RF microneedling) → sometimes useful for mixed scar types but less effective for purely raised scars.
Comparison Overview
| Combination | Best For | Key Consideration |
|---|---|---|
| Steroid + 5-FU | Thick, resistant keloids | May sting during injection |
| Steroid + Cryo | Nodular keloids (shoulders) | Risk of pigmentation changes |
| Steroid + PDL | Hypertrophic scars + redness | Multiple sessions required |
Key Point: Steroid injections are often more effective when integrated into a multi-modal treatment plan. The right combination depends on your scar’s characteristics, your skin type, and your doctor’s clinical judgment.
Cost of Steroid Injections in Singapore
The cost of steroid injections for raised acne scars in Singapore varies. It depends on the clinic setting, the size and number of scars, the number of sessions required, and whether treatment is combined with other modalities.
Factors That Influence Cost
- Scar complexity → larger or thicker scars may require more steroid or multiple injection points
- Number of sessions → most patients need several treatments spaced a few weeks apart
- Treatment modality → costs rise if injections are combined with therapies such as 5-FU, cryotherapy, or laser
- Clinic setting → public hospitals may be subsidised, while private clinics often provide faster access and more tailored care
- Additional services → items such as anaesthetic cream, dressings, or scar care products may be billed separately
Estimated Per-Session Costs
| Clinic Type | Estimated Cost (SGD) | Typical Inclusions |
|---|---|---|
| Public hospital | $30 – $80 | Subsidised steroid injection |
| Private dermatologist | $120 – $250+ | Consultation, injection, follow-up review |
| Aesthetic clinic | $150 – $300+ | May include anaesthetic, aftercare advice, and photo documentation |
Package Pricing
| Package Type | Price Range (SGD) | Typical Inclusions |
|---|---|---|
| 3-session plan | $350 – $650 | Series of steroid injections |
| 6-session plan | $750 – $1,200 | Injections, reviews, and basic aftercare |
| Combination package | $1,000 – $2,000+ | Steroid injections with laser or 5-FU therapy |
Other Potential Costs
- Initial consultation: $40 – $150
- Topical anaesthetic (if used): $10 – $30 per session
- Silicone gel or sheets: $50 – $80 per item
Is It Cost-Effective?
For hypertrophic scars, steroid injections may reduce the need for more invasive or costly procedures later. Keloid scars usually require longer or combination therapy, which increases overall cost but helps achieve more stable results. Package plans can offer better value, though inclusions differ across clinics and should be confirmed in advance.
Frequently Asked Questions (FAQs)
How painful are steroid injections?
Most patients describe a quick prick followed by mild pressure or ache. Discomfort is short-lived and can be reduced with numbing cream or local anaesthetic.
See details in the procedure overview.
How many sessions are usually needed?
Hypertrophic scars often improve in 2–4 sessions, while keloids usually need more treatments or maintenance injections.
See the full treatment plan in the procedure overview.
Are steroid injections safe for all skin types?
Yes. They can be used across all skin types, but darker tones have a higher chance of pigment changes. Doctors adjust dose and depth, and recommend strict sun protection.
More on this in suitability and skin profile.
Will scars come back after treatment?
Hypertrophic scars may flatten permanently. Keloids have a higher chance of recurrence, often needing ongoing or combination therapy.
See the benefits and limitations.
When will I see results?
Minor softening may be visible after 1–2 weeks. More noticeable flattening usually appears after 2–4 sessions, with keloids taking longer.
See treatment expectations.
Can I resume skincare or makeup after treatment?
Avoid active products like retinoids or acids for 3–5 days. Light, non-comedogenic makeup can be used after 24 hours if the skin is calm.
See aftercare and recovery.
Is the treatment permanent?
For hypertrophic scars, improvement is often long-lasting. Keloids may recur, so maintenance or combined treatments are sometimes needed.
Can steroid injections be combined with other treatments?
Yes. Common combinations include steroids with 5-FU for thick keloids, PDL laser for redness, and silicone gels or sheets for long-term support.
See alternatives and combination treatments.
Conclusion: Choosing the Right Acne Scar Treatment
Raised acne scars can affect both comfort and confidence. Steroid injections are an established treatment for hypertrophic and keloid scars in Singapore. They help scars soften, flatten, and ease symptoms such as itch or tightness. However, outcomes differ between patients, and keloids in particular may recur, making injections more suitable as part of a long-term management plan rather than a one-time fix.
You may consider steroid injections if your scars are raised, firm, expanding, or still active. A medical consultation ensures proper scar assessment, adjustment for your skin profile, and a tailored treatment plan. With timely treatment, consistent aftercare, and regular follow-up, many patients see gradual and lasting improvements.
Under the guidance of doctors experienced in acne scar management, such as Dr. Justin Boey at Sozo Aesthetic Clinic, patients can expect a treatment plan that prioritises safety, effectiveness, and adaptation to Singapore’s diverse skin types.
