21 Aug Retatrutide and Acne Singapore: Can It Cause Breakouts
Retatrutide and Acne in Singapore: Can Weight Loss Injections Cause Breakouts?
By Dr Rachel Ho | Aesthetic Doctor, Founder, The Skin Longevity Clinic, Singapore
Updated August 2026
Retatrutide has attracted considerable attention following Phase 3 weight loss results, and patients are now asking whether it can also cause acne. Current evidence does not establish retatrutide as a direct acne trigger.
Publicly released Phase 3 data list nausea, diarrhoea, constipation, vomiting and altered skin sensation among the more frequently reported adverse effects. Acne was not listed among the common adverse events, although the trials were not designed specifically to detect or investigate acne1.
A breakout that begins during weight loss still deserves proper assessment. Pre-existing hormonal acne, changes in skincare or supplements, folliculitis, an injection reaction and an unverified product can all coincide with the same timeline.
Retatrutide and acne at a glance
FAQ about retatrutide
| FAQ about retatrutide | Evidence based answer |
|---|---|
| Does retatrutide directly cause acne? | Current evidence has not established a direct causal link |
| Was acne a common Phase 3 side effect? | Acne was not included among the commonly reported adverse events in TRIUMPH-1 |
| Can acne appear during major weight loss? | Yes, although the timing does not prove that the medication caused it |
| Can incretin treatment improve acne? | Some patients report improvement, but the evidence is observational and not specific to retatrutide |
| Is retatrutide available in Singapore? | Retatrutide remains investigational and unavailable for public prescribing |
| Can retatrutide bought online be trusted? | Products sold outside authorised trials cannot be verified for identity, concentration, purity or sterility |
| What should be treated first? | Active acne should be controlled before pigmentation or acne scar treatment begins |
What is retatrutide?
Retatrutide is an investigational once weekly injection that activates the GIP, GLP-1 and glucagon receptors. This triple receptor action influences appetite, glucose regulation and energy metabolism2.
In the manufacturer reported TRIUMPH-1 Phase 3 results, participants receiving 12 mg lost an average of 28.3 percent of their body weight at 80 weeks under the efficacy analysis1. Detailed peer reviewed publication remains important for evaluating the complete results, subgroup findings and less common adverse events.
Retatrutide has not been approved by any regulatory authority and is legally available only through authorised Lilly clinical trials. It cannot currently be prescribed or supplied as routine weight management treatment in Singapore2.
Retatrutide and acne at a glance. Acne was not listed among the commonly reported Phase 3 adverse events, retatrutide remains investigational in Singapore, and any active breakout should be treated before acne marks or scars.
Does retatrutide cause acne?
Retatrutide-specific evidence is currently insufficient to answer this with certainty. Acne has not been reported as one of the main adverse effects in the public TRIUMPH-1 data, but the absence of acne from a topline list does not prove that no participant developed a breakout1.
A 2024 review examined 45 publications involving six established GLP-1 receptor agonists. The authors found no conclusive evidence that these medicines directly caused acne and noted that dedicated dermatological studies were limited3.
That review did not include meaningful retatrutide-specific acne data. Retatrutide has an additional glucagon receptor action and remains investigational, so evidence from semaglutide or liraglutide cannot simply be transferred to it.
Why can breakouts appear during a weight loss journey? Possible explanations include a pre-existing acne pattern, changes in supplements or skincare, folliculitis, local irritation and exposure to an unverified product. Timing alone does not prove that a medication caused the breakout.
Why can acne appear during a weight loss journey?
The timing of a breakout can create a strong impression that a new medication caused it. Several other explanations should be considered before reaching that conclusion.
A pre-existing acne pattern can flare
Adult female acne, hormonal acne and comedonal acne can fluctuate over time. A flare that begins after a treatment starts can still reflect the person’s underlying acne biology rather than a direct drug reaction.
Diet, supplements and skincare often change at the same time
People beginning a weight management programme commonly change their meals, protein supplements, vitamins, exercise routine and skincare together. Introducing several variables at once makes it difficult to identify which change coincided with the breakout.
Folliculitis can look like acne
Folliculitis often produces many small, similar bumps, sometimes with itching. Acne more commonly includes a mixture of blackheads, whiteheads, inflamed papules, pustules and deeper nodules.
An injection reaction can be mistaken for a pimple
Local redness, swelling, tenderness or itching around an injection site represents a different process from facial acne. Retatrutide trials have also reported dysesthesia, which describes altered sensations such as burning, tingling or unusual skin sensitivity without typical acne lesions1.
The product might not be retatrutide
Anything currently sold as retatrutide outside an authorised Lilly trial is an unapproved and unverifiable product. Its contents can include an incorrect dose, contaminants, impurities or a different substance, so a skin reaction cannot confidently be attributed to authentic retatrutide2.
Can GLP-1 therapy improve or worsen acne? Research has not shown a consistent acne-worsening signal. Some users report improvement, but the evidence is observational and direct retatrutide data remain limited
Can GLP-1 treatment improve acne?
Improvement is also possible in selected patients. A 2026 survey involving 1,226 people receiving weight management treatment found that 17 of 41 respondents with pre-existing acne reported improvement while taking at least one GLP-1 receptor agonist4.
The finding is interesting but preliminary. The acne subgroup was small, outcomes were self reported and the study was not designed to prove that the medicine treated acne. Retatrutide was not assessed as a separate acne treatment.
The balanced conclusion is that incretin based therapy has not shown a consistent acne worsening signal. Some patients improve, some experience unrelated flares, and retatrutide-specific evidence remains absent.
Is it acne or another skin reaction?
Acne or another diagnosis?
| Appearance or symptom | More likely explanation |
|---|---|
| Blackheads, whiteheads and mixed inflamed bumps on the face, chest or back | Acne vulgaris |
| Numerous uniform itchy bumps around hair follicles | Folliculitis |
| Localised swelling, redness or itching where an injection was given | Injection site reaction |
| Burning, tingling or tenderness without visible acne lesions | Dysesthesia |
| Dry, stinging or peeling skin after adding several active products | Irritant dermatitis |
| Hives, facial swelling or breathing difficulty | Possible allergic reaction requiring urgent care |
Photographs and an examination are more reliable than trying to diagnose the eruption from its timing alone.
What should you do if acne starts during weight loss treatment?
1. Confirm what you are taking
Approved weight management medication should come from a licensed prescriber and regulated pharmacy. Further doses of a product sold as retatrutide outside a recognised clinical trial should be withheld until the vial and symptoms have been reviewed by a licensed doctor2.
Keep the packaging, batch information, receipt and seller details. These records are useful when the product’s identity or storage history is uncertain.
2. Simplify the skincare routine
Use a gentle cleanser, a non-comedogenic moisturiser and broad spectrum sunscreen. Pause scrubs, abrasive devices and repeated layering of strong acids when the skin is irritated.
A simple routine makes the acne easier to assess and reduces the risk of post inflammatory hyperpigmentation, which is especially relevant in Asian skin.
3. Treat the type of acne present
Current acne guidelines support treatments such as topical retinoids, benzoyl peroxide and suitable combinations, with oral treatment considered for more extensive disease. Azelaic acid can be useful when acne and brown post acne marks occur together5.
Pregnancy, breastfeeding, skin sensitivity and other medicines can change which options are suitable. Prescription treatment should follow a medical assessment.
4. Seek treatment before scars form
Painful nodules, cysts, widespread inflammation or acne leaving indented scars deserves early medical care. Repeatedly changing cosmetic serums while inflammation continues can delay effective treatment and increase the risk of persistent marks and scarring.
At The Skin Longevity Clinic, active acne is controlled before pigment laser, RF microneedling, subcision or other acne scar procedures are planned. This sequence is consistent with the clinic’s wider approach to acne marks and scars, where inflammation comes first, pigment second and structural scarring last.
Can acne treatment continue during approved GLP-1 therapy?
Acne treatment can usually proceed while a patient is receiving a properly prescribed weight management medicine. The treatment plan should still consider hydration, nutritional intake, gastrointestinal symptoms, pregnancy planning and the rest of the medication list. Acne treatment such as medication and treatments like selective ablation of sebaceous glands, Q-switched laser, chemical peels and LED light.
Medication changes should remain with the prescribing doctor. A skin concern can often be treated directly without stopping a metabolically useful medicine.
Dr Rachel Ho’s clinical perspective
I would not diagnose retatrutide acne from timing alone. I would first establish whether the eruption is comedonal acne, inflammatory acne, folliculitis, dermatitis or an injection related reaction, because each requires a different treatment.
The source of the medicine is equally important. Authentic trial medication has controlled manufacturing, dosing and monitoring, while a black market vial provides no dependable information about what entered the body.
For most patients, the useful question is not simply whether the breakout started after a weight loss injection. It is what the eruption actually is, what else changed and how quickly we can control inflammation before marks or scars develop.
Retatrutide, acne and The Skin Longevity Clinic
The Skin Longevity Clinic does not prescribe, supply or source retatrutide because it remains an investigational medicine. The clinic can assess acne, injection related skin reactions, post inflammatory pigmentation and acne scars while medication decisions remain with the patient’s licensed weight management prescriber.
The Skin Longevity Clinic is located at 9 Scotts Road, #06-05 Scotts Medical Center at Pacific Plaza, Singapore 228210, near Orchard Road.
Frequently asked questions
Does retatrutide cause acne?
Current evidence has not established retatrutide as a direct acne trigger. Public Phase 3 data do not list acne among the common adverse events, while dedicated retatrutide acne studies are lacking1.
Can GLP-1 weight loss medicines improve acne?
Some patients with pre-existing acne have reported improvement, but the evidence is observational and cannot prove a treatment effect. Established acne medication remains more appropriate when active acne requires treatment4,5.
Should I stop an approved GLP-1 medicine because of acne?
The prescribing doctor should review any medication decision. Acne can often be treated without stopping a beneficial metabolic treatment, provided the eruption has been correctly diagnosed.
What should I do if I bought retatrutide online or in Malaysia?
Current retatrutide products sold outside authorised Lilly trials are unapproved and unverifiable. Further injections should wait until a licensed doctor has reviewed the product, symptoms and relevant medical risks2.
Can retatrutide acne leave scars?
Any severe or prolonged inflammatory acne can leave post inflammatory pigmentation and permanent scars. Early acne control is therefore more useful than waiting to see whether the breakout settles by itself.
Related reading at TheSkinLongevityClinic.com
Readers can continue with:
Comprehensive Guide to Acne Treatments
Acne Marks vs Acne Scars: PIH Treatment in Singapore and When Pico Laser Helps
Acne Scar Treatment in Singapore: The Complete Doctor’s Guide
GLP-1 Skin Changes and Skin Longevity in Singapore
Skin Longevity Assessment in Singapore
References
- Eli Lilly and Company. TRIUMPH-1 Phase 3 Topline Results. 2026.
- Eli Lilly and Company. What to Know About Retatrutide. Updated July 2026.
- Ogunremi OO, Ismail SF, Dhami RK, et al. A Meta-analysis of the Incidence of Acne Vulgaris in Patients Treated With GLP-1 Agonists. International Journal of Women’s Dermatology. 2024. PMID 38586157.
- Rao S, Midura I, Santiago Mangual KP, et al. Skin Impacts and Tradeoffs of GLP-1 Therapy. Dermatology and Therapy. 2026. PMID 42579223.
- Reynolds RV, et al. Guidelines of Care for the Management of Acne Vulgaris. Journal of the American Academy of Dermatology. 2024. PMID 38300170.
- Jastreboff AM, et al. Triple Hormone Receptor Agonist Retatrutide for Obesity. New England Journal of Medicine. 2023. PMID 37366315.