Aleppo soap has a short ingredient list: olive oil, laurel berry oil, water and lye. That simplicity is part of its appeal, but it does not make the soap risk-free. Like any true soap it is alkaline, and one of its two oils contains known allergens.
This guide covers the side effects people actually report, what the research says about pH and laurel oil, who should be careful, and how to patch test a new bar. For the full ingredient picture, see our ingredients guide.
Key takeaways
- True soap is alkaline. Most bathing soaps measure pH 9-10 (Tarun et al., 2014).
- The skin surface is acidic, usually below pH 5 (Lambers et al., 2006, via Wikipedia).
- Laurel oil contains contact allergens, with moderate sensitising potency (Altmeyers Encyclopedia).
- Daisy-family allergies matter: cross-reactions with laurel are reported.
- Patch test for 7-10 days, adapting the American Academy of Dermatology's advice.
The short answer
Aleppo soap's most common side effect is a tight or dry feeling, because, like all true soap, it is alkaline (around pH 9-10). Less often, people react to the laurel berry oil, which contains known contact allergens. Anyone with a laurel or daisy-family allergy, a skin condition, or a baby to wash should ask a doctor first, and everyone should patch test a new bar.
Is Aleppo soap too alkaline?
All true soap is alkaline, because it is made by reacting oils with lye. A 2014 study of bathing soaps found most measured pH 9-10, while most shampoos measured pH 6-7 (Tarun et al., 2014). Natural skin surface pH, by contrast, averages below 5 (Lambers et al., 2006, via Wikipedia).
Aleppo soap sits in the same range as other true soaps; being handmade does not change its chemistry. If your skin feels tight after washing, the usual responses are to wash less often, rinse well and avoid very hot water. Hard water can add to the feeling by leaving soap scum behind (USGS). For how Aleppo soap compares with other bars, see Aleppo soap vs regular soap.
Pro Tip: "pH-balanced" and "true soap" do not go together. A bar sold as pH 5.5 is a syndet (a synthetic detergent bar), not a traditional soap. Neither is automatically better; they are simply different products.
Laurel oil: the ingredient to know about
Laurel berry oil gives Aleppo soap its scent, and it is also the ingredient most likely to cause a reaction. Laurel oil contains several sesquiterpene lactones, including costunolide and dehydrocostus lactone, which are recognised contact allergens. Altmeyers Encyclopedia rates its sensitising potency as moderate and sensitisation as occasional (Altmeyers Encyclopedia). Allergic contact dermatitis caused by laurel leaf and oil has also been described in the medical literature (Thermo Fisher Allergen Encyclopedia).
Cross-reactions with daisy-family plants
People sensitised to laurel can cross-react with plants of the daisy family (Compositae), such as parthenolide from feverfew and alantolactone from elecampane (Altmeyers Encyclopedia). If you know you react to these plants, or to bay leaves, talk to a doctor before using any laurel soap.
Does a higher laurel percentage matter?
We found no study comparing reactions across laurel strengths. What is certain is that a higher percentage means more laurel oil in the bar, and that a Pure Olive bar contains none. Our guide to the laurel oil percentage explains what changes between strengths.
What about the olive oil?
Olive oil allergy is uncommon, but olive oil is not as gentle as its reputation suggests. In a 2013 trial, 19 adults applied raw olive oil to their forearms twice a day for four to five weeks, and the researchers found it weakened the skin barrier, unlike sunflower seed oil (Danby et al., 2013). That study used raw oil left on the skin, not soap that is rinsed off, so it does not tell us how Aleppo soap behaves. It is a reminder that "natural" is not the same as "risk-free". Our article on Aleppo soap benefits looks at the evidence in both directions.
Keep it out of your eyes
Because it is alkaline, Aleppo soap stings if it gets into the eyes. Rinse with plenty of clean water and seek medical help if irritation lasts. This is one reason we do not suggest using it on or near the face.
Who should talk to a professional first
| Situation | What to do |
|---|---|
| Known reaction to bay laurel | Avoid laurel bars; ask a doctor before trying any Aleppo soap |
| Allergy to daisy-family plants | Ask a doctor first; cross-reactions with laurel are reported |
| A skin condition or very sensitive skin | Talk to a dermatologist before changing soap |
| Babies and young children | Ask a doctor or health visitor first |
| Skin feels tight after washing | Wash less often, rinse well and avoid very hot water |
| Redness, itching or a rash | Stop, rinse well and seek advice if it persists |
| Soap in the eyes | Rinse with plenty of clean water; seek help if irritation lasts |
| No known sensitivities | Patch test, then choose any strength by scent |
- Anyone with a known laurel or daisy-family allergy.
- Anyone with a skin condition or very sensitive skin. A dermatologist can advise on what to use.
- Parents of babies and young children. There is no research on Aleppo soap and babies, and Alepo makes no claims for that use.
- Anyone who has reacted to a soap before and does not know which ingredient caused it.
Not sure where to start? Our Pure Olive bar contains no laurel oil, and our soap collection lets you compare strengths. Patch test first, whichever you choose.
How to patch test a new bar
The American Academy of Dermatology suggests testing new products on a small patch of skin, such as the inside of the forearm or the bend of the elbow, twice a day for 7-10 days, and stopping if a reaction appears (AAD). That advice is written for leave-on products. For a rinse-off soap, the practical equivalent is to wash a small area:
- Pick a spot on the inside of the forearm or the bend of the elbow.
- Wash it with a small amount of lather once or twice a day, then rinse.
- Keep going for 7-10 days.
- Watch for redness, itching, swelling or a rash.
- If it reacts, rinse well, stop using the soap and see a doctor if it does not settle.
Pro Tip: Patch test one new product at a time. If you start a new soap, shampoo and lotion in the same week and react, you will not know which one caused it.
Fake bars can add extra risks
A traditional bar has nothing beyond its oils, water and lye. Imitations may add fragrance or colourants; in 2010 an exporter told The National that cheap copies used chemical colouring (The National, 2010). Every extra ingredient is one more thing to react to, so read the label. Our guide on how to spot fake Aleppo soap has seven quick checks.
Frequently asked questions
Does 100% natural mean Aleppo soap is suitable for everyone?
No. Natural ingredients can still cause irritation or allergic reactions, and a short ingredient list is not a guarantee of suitability. The laurel percentage describes the recipe, not a medical benefit or a recommended skin type. Follow the product’s directions and avoid ingredients you know you react to. ALEPO does not claim to treat skin conditions.
What is the pH of ALEPO soap?
True soap is alkaline, but we do not publish a batch-specific pH measurement for ALEPO here. A general pH range quoted for other soaps is not a test result for your bar. Neither a natural ingredient list nor a higher laurel percentage makes a soap pH-neutral. Request product-specific information if a measured pH matters to your choice.
What should I do if soap causes irritation?
Stop using the product and rinse the affected area with water. If irritation persists, or you develop a rash, seek medical advice. Natural oils can still trigger reactions; do not keep using a bar on the assumption that discomfort is a normal adjustment. Keep the packaging and batch details if you need to report a product concern.
Does Aleppo soap treat eczema, acne or other skin conditions?
ALEPO does not claim that its bars treat eczema, acne or any other skin condition. Traditional use and studies on individual oils do not establish that a finished soap treats a condition. Do not choose a laurel percentage as a treatment dose or replace prescribed care with soap. Ask a qualified healthcare professional about a product suitable for your condition.
The bottom line
Aleppo soap is a true soap, so it is alkaline and can leave skin feeling tight. Its laurel oil contains known contact allergens, with cross-reactions to daisy-family plants. If you have no known sensitivities, a patch test is a sensible first step; anyone with allergies, a skin condition or a baby to wash should ask a professional first.
If you are cautious about laurel, start with a bar that has none or little of it, and build from there. For everyday questions, see what Aleppo soap is, how to use Aleppo soap and why Aleppo soap is cured.
Choose your strength. From laurel-free Pure Olive to 10%, 20% and 40% laurel, with the percentage stated on every bar. See all Aleppo soaps. Free EU shipping over €50.
Related reading: the best Aleppo soap brands, where to buy Aleppo soap and the history of Aleppo soap.
This article is for general information and is not medical advice. If you have a skin condition, an allergy or a reaction, talk to a doctor or pharmacist.
Sources
- Tarun J. et al. "Evaluation of pH of bathing soaps and shampoos for skin and hair care." Indian Journal of Dermatology, 2014. https://doaj.org/article/b16ff7fe3e7a4ddb92ebb672cfe1c476
- Lambers H. et al. "Natural skin surface pH is on average below 5." International Journal of Cosmetic Science, 2006 (summarised in Wikipedia, "Acid mantle"). https://en.wikipedia.org/wiki/Acid_mantle
- Altmeyers Encyclopedia. "Laurel, genuine." https://www.altmeyers.org/en/naturopathy/laurel-of-genuine-142917
- Thermo Fisher Scientific. Allergen Encyclopedia, "Bay leaf" (f278). https://www.thermofisher.com/phadia/gb/en/resources/allergen-encyclopedia/f278.html
- American Academy of Dermatology. "How to test skin care products before use." 2021. https://www.aad.org/news/how-to-test-skin-care-products-before-use
- Danby S.G. et al. "Effect of olive and sunflower seed oil on the adult skin barrier." Pediatric Dermatology, 2013. https://research.lstmed.ac.uk/en/publications/effect-of-olive-and-sunflower-seed-oil-on-the-adult-skin-barrier--2/
- U.S. Geological Survey, Water Science School. "Hardness of water." https://www.usgs.gov/special-topics/water-science-school/science/hardness-water
- The National. "Market awash with imitations." 30 October 2010. https://www.thenationalnews.com/business/money/market-awash-with-imitations-1.512005
