Lactic Acid Drug Interactions, Uses, Effectiveness, Safety & More
What is this page for?
First and foremost: how Lactic Acid interacts with medications. The heart of this page is the interaction list — every drug Lactic Acid is known to interact with, and how serious each one is.
But these pages have grown well beyond that into a full monograph — what Lactic Acid is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy
Check Lactic Acid against your medication
Add one medicationDrugs that interact with Lactic Acid
0 medications have a known interaction with Lactic Acid, graded by severity. Select any drug for the full evidence-based detail.
We don’t currently list any known drug interactions for Lactic Acid. This doesn’t guarantee none exist — always confirm with your pharmacist before combining supplements with your medications.
What Severity, Likelihood & Evidence Mean
Severity — How Serious It Can Be
- Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
- Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
- Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
- No known interaction. Checked against our sources with nothing documented — not the same as proven safety.
Likelihood — How Well It’s Documented
- Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
- Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
- Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
- Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Where This Data Comes From
- Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
- Each drug listed above links to the full report for that exact Lactic Acid combination — clinical detail, likelihood, evidence level, and citations.
- Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
Lactic Acid: Uses, Safety & Side Effects
Lactic acid is a naturally occurring acid made by the body during exercise and by bacteria that ferment milk and other foods. It is most often used on the skin as an exfoliant and moisturizer and in some vaginal products to support normal pH. While topical skin uses are well established, evidence for swallowing lactic acid supplements for health benefits is limited, so check with a pharmacist before using it.
- Common forms
- Topical creams and lotions, chemical peels, oral capsules, foods (fermented dairy), suppositories, mouth rinses
- Skin exfoliation and anti-aging
- Moisturizing dry skin
- Maintaining vaginal pH
- Acne and skin texture
- Ingredient in fermented foods
Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.
Generally safe in foods and skin products, but strong concentrations can irritate skin and mucous membranes.
When used topically in appropriate concentrations . There is insufficient reliable information available about the safety of lactic acid when used ora...
Read the full pregnancy detailWhen used topically in appropriate concentrations . There is insufficient reliable information available about the safety of lactic acid when used ora...
Read the full breastfeeding detailPregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Overview
Lactic acid is a natural acid that the body makes in muscles during hard exercise and that bacteria make when they ferment sugars. It is the substance that gives sour milk, yogurt, sauerkraut, and sourdough bread their tangy taste.
In supplements and consumer products, lactic acid is usually made by fermenting carbohydrates like corn or beets with bacteria. It is one of a group of compounds called alpha hydroxy acids (AHAs) that are widely used in skin care.
People most commonly meet lactic acid in skin creams, peels, and moisturizers, in some vaginal health products, and as a natural part of fermented foods. It is also used as a food preservative and flavoring.
How it works
On the skin, lactic acid works as an alpha hydroxy acid. It loosens the bonds that hold dead skin cells together, helping them shed so newer, smoother skin shows. It also draws and holds water, which helps the skin feel more hydrated.
In the vagina and gut, lactic acid is produced by helpful Lactobacillus bacteria and lowers the pH, creating an acidic environment that may make it harder for some unwanted microbes to grow.
Much of the detailed understanding of these effects comes from laboratory studies and skin research. The way lactic acid behaves can depend a lot on its concentration and the pH of the product.
Does Lactic Acid work?
How to read these evidence grades
Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.
Likely Effective Dry skin
Topical lactic acid, as lactate, lactic acid, or ammonium lactate, improves the severity of dry skin.
Also studied for 9 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Acne
Topical lactic acid has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Aging skin
Preliminary clinical research shows that topical lactic acid seems to reduce wrinkles and other signs of aging and photodamage.
Insufficient Reliable Evidence To Rate Bacterial vaginosis
It is unclear if intravaginal lactic acid is beneficial for bacterial vaginosis.
Insufficient Reliable Evidence To Rate Canker sores
It is unclear if a mouthwash containing lactic acid is beneficial for canker sores.
Insufficient Reliable Evidence To Rate Melasma
It is unclear if topical lactic acid is beneficial for melasma.
Insufficient Reliable Evidence To Rate Onychomycosis
Topical lactic acid has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Seborrheic dermatitis
Topical lactic acid has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Urinary tract infections (UTIs)
It is unclear if intravaginal lactic acid is beneficial for UTI prevention.
Insufficient Reliable Evidence To Rate Water warts
Topical lactic acid has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.
Safety & precautions
Lactic acid is a normal part of the body and of many foods, so eating it in foods like yogurt is considered safe for most people. As a skin product, it is generally well tolerated when used as directed.
Stronger concentrations, such as professional peels, can cause irritation, burning, and increased sensitivity to the sun. People with sensitive skin or skin conditions should be cautious and may want to test a small area first.
Pregnancy and breastfeeding: Lactic acid in normal food amounts is generally considered fine. However, the safety of concentrated skin peels or vaginal products has not been well studied in these groups, so it is best to check with your doctor or pharmacist before using them.
If you have any chronic medical condition or use prescription skin treatments, talk to a healthcare professional before adding lactic acid products.
Side effects
On the skin, lactic acid can cause redness, stinging, burning, itching, dryness, or peeling, especially at higher strengths or with frequent use. It can also make your skin more sensitive to sunlight, so daily sunscreen is recommended.
Vaginal products may cause mild irritation in some people. Eating foods with lactic acid rarely causes problems beyond their normal taste.
Serious reactions are uncommon, but stop using a product and seek care if you develop severe burning, blistering, swelling, or signs of an allergic reaction.
Lactic Acid: Reported Adverse Effects
Documented safety reports on Lactic Acid from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.
Topically, intravaginally, and as a mouthwash, lactic acid is generally well tolerated.
Most Common Adverse Effects:
Topically: Mild irritation, sun sensitivity, and a tingling sensation.
Serious Adverse Effects (Rare):
Topically: Increased risk of skin cancer, skin damage, and transient hyperpigmentation. With the use of higher concentrations, bleeding, blistering, burns, itching, redness, severe irritation, and skin discoloration with sloughing, stinging, and swelling.
Burns Dermatologic
Topically, lactic acid is generally well tolerated when used in concentrations at or below 10% and applied to the face or 15% and applied elsewhere. In general, products should be tested on a small area of skin before applying it to a larger area.
Alpha hydroxy acids like lactic acid can increase sensitivity to the sun and ultraviolet (UV) light. This can increase damage to the skin, and after long-term use, might increase the risk of skin cancer. These effects can be mitigated by using sunscreen and/or protective clothing.
Adverse reactions to alpha hydroxy acids like lactic acid can range from mild irritation, a tingling sensation, and stinging, to severe redness, swelling, itching, blistering, bleeding, rash, burns, and skin discoloration.
Nail discoloration, nail detachment, and nail softness, as well as irritation, pain, and redness at the application site were reported in a clinical trial investigating the topical use of a specific nail product (K101) containing lactic acid, urea, and propylene glycol. It is unclear if these effects are due to lactic acid, other ingredients, or the combination.
- Kempers S, Katz HI, Wildnauer R, Green B. An evaluation of the effect of an alpha hydroxy acid-blend skin cream in the cosmetic improvement of symptoms of moderate to severe xerosis, epidermolytic hyperkeratosis, and ichthyosis. Cutis 1998;61:347-50.
- Stiller MJ, Bartolone J, Stern R, et al. Topical 8% glycolic acid and 8% L-lactic acid creams for the treatment of photodamaged skin. A double-blind, vehicle-controlled clinical trial. Arch Dermatol 1996;132:631-6.
- Wehr R, Krochmal L, Bagatell F, Ragsdale W. A controlled two-center study of lactate 12 percent lotion and a petrolatum-based creme in patients with xerosis. Cutis 1986;37:205-7, 209.
- Rogers RS 3rd, Callen J, Wehr R, Krochmal L. Comparative efficacy of 12% ammonium lactate lotion and 5% lactic acid lotion in the treatment of moderate to severe xerosis. J Am Acad Dermatol 1989;21(4 Pt 1):714-6.
- Jennings MB, Logan L, Alfieri DM, Ross CF, Goodwin S, Lesczczynski C. A comparative study of lactic acid 10% and ammonium lactate 12% lotion in the treatment of foot xerosis. J Am Podiatr Med Assoc 2002;92(3):143-8.
- Dahl MV, Dahl AC. 12% lactate lotion for the treatment of xerosis. A double-blind clinical evaluation. Arch Dermatol 1983;119(1):27-30.
- Pham HT, Exelbert L, Segal-Owens AC, Veves A. A prospective, randomized, controlled double-blind study of a moisturizer for xerosis of the feet in patients with diabetes. Ostomy Wound Manage 2002;48(5):30-6.
- Draelos ZD, Hall S, Munsick C. A 14-day Controlled Study Assessing Qualitative Improvement with 15% Lactic Acid and Ceramides in Skin Moisturization and Desquamation. J Clin Aesthet Dermatol 2020;13(8):E54-E58.
- Jennings MB, Alfieri D, Ward K, Lesczczynski C. Comparison of salicylic acid and urea versus ammonium lactate for the treatment of foot xerosis. A randomized, double-blind, clinical study. J Am Podiatr Med Assoc 1998;88(7):332-6.
- Ademola J, Frazier C, Kim SJ, Theaux C, Saudez X. Clinical evaluation of 40% urea and 12% ammonium lactate in the treatment of xerosis. Am J Clin Dermatol 2002;3(3):217-22.
- Jennings MB, Alfieri DM, Parker ER, Jackman L, Goodwin S, Lesczczynski C. A double-blind clinical trial comparing the efficacy and safety of pure lanolin versus ammonium lactate 12% cream for the treatment of moderate to severe foot xerosis. Cutis 2003;71
- Uy JJ, Joyce AM, Nelson JP, West B, Montague JR. Ammonium lactate 12% lotion versus a liposome-based moisturizing lotion for plantar xerosis. A double-blind comparison study. J Am Podiatr Med Assoc 1999;89(10):502-5.
- US Food and Drug Administration (FDA). Cosmetic Ingredients: Alpha Hydroxy Acids. August 2020. Available at: https://www.fda.gov/cosmetics/cosmetic-ingredients/alpha-hydroxy-acids. Accessed on October 19, 2021.
- Kurtzweil P. Alpha-hydroxy acids for skin care: Smooth sailing or rough seas? FDA 1999. Available at: /www.fda.gov/fdac/features/1998/298_ahas.html (Accessed 18 August 2000).
- Emtestam L, Svensson Å, Rensfeldt K. Treatment of seborrhoeic dermatitis of the scalp with a topical solution of urea, lactic acid, and propylene glycol (K301): results of two double-blind, randomised, placebo-controlled studies. Mycoses. 2012 Sep;55(5):3
- Köse O, Özmen I, Arca E. An open, comparative study of 10% potassium hydroxide solution versus salicylic and lactic acid combination in the treatment of molluscum contagiosum in children. J Dermatolog Treat. 2013 Aug;24(4):300-4.
- Diebold R, Schopf B, Stammer H, Mendling W. Vaginal treatment with lactic acid gel delays relapses in recurrent urinary tract infections: results from an open, multicentre observational study. Arch Gynecol Obstet 2021;304(2):409-417.
- Khattar JA, Musharrafieh UM, Tamim H, Hamadeh GN. Topical zinc oxide vs. salicylic acid-lactic acid combination in the treatment of warts. Int J Dermatol 2007;46(4):427-30.
- Siskin SB, Quinlan PJ, Finkelstein MS, Marlucci M, Maglietta TG, Gibson JR. The effects of ammonium lactate 12% lotion versus no therapy in the treatment of dry skin of the heels. Int J Dermatol 1993;32(12):905-7.
- Robinson D, Friedmann D, Gordon J, Wortzman M, Nelson D. Efficacy and Tolerability of a Double-Conjugated Retinoid and Alpha Hydroxy Acid Cream in Subjects With Mild to Moderate Blemish-Prone Skin. J Drugs Dermatol 2022;21(1):54-59.
- Emtestam L, Kaaman T, Rensfeldt K. Treatment of distal subungual onychomycosis with a topical preparation of urea, propylene glycol and lactic acid: results of a 24-week, double-blind, placebo-controlled study. Mycoses 2012;55(6):532-40.
Adverse-effects data: Natural Medicines, Therapeutic Research Center
Dosing
There is no single standard dose of lactic acid, because it is used in so many different ways. Skin products commonly contain a range of concentrations, and professional peels use stronger amounts applied by trained providers.
For any product, the best approach is to follow the label directions and start slowly to see how your skin reacts. For vaginal or oral products, use exactly as directed on the package.
Because the right amount depends on the product and your individual situation, check with a pharmacist or doctor if you are unsure how to use it safely.
Lactic Acid & Pregnancy
Lactic Acid & Breastfeeding
© 2026 Therapeutic Research Center
Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center
References & further reading
The 21 references that drive our Lactic Acid monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- Kempers S, Katz HI, Wildnauer R, Green B. An evaluation of the effect of an alpha hydroxy acid-blend skin cream in the cosmetic improvement of symptoms of moderate to severe xerosis, epidermolytic hyperkeratosis, and ichthyosis. Cutis 1998;61:347-50.
- Stiller MJ, Bartolone J, Stern R, et al. Topical 8% glycolic acid and 8% L-lactic acid creams for the treatment of photodamaged skin. A double-blind, vehicle-controlled clinical trial. Arch Dermatol 1996;132:631-6.
- Wehr R, Krochmal L, Bagatell F, Ragsdale W. A controlled two-center study of lactate 12 percent lotion and a petrolatum-based creme in patients with xerosis. Cutis 1986;37:205-7, 209.
- Kurtzweil P. Alpha-hydroxy acids for skin care: Smooth sailing or rough seas? FDA 1999. Available at: /www.fda.gov/fdac/features/1998/298_ahas.html (Accessed 18 August 2000). DOI
- Emtestam L, Svensson Å, Rensfeldt K. Treatment of seborrhoeic dermatitis of the scalp with a topical solution of urea, lactic acid, and propylene glycol (K301): results of two double-blind, randomised, placebo-controlled studies. Mycoses. 2012 Sep;55(5):3 PubMed
- Köse O, Özmen I, Arca E. An open, comparative study of 10% potassium hydroxide solution versus salicylic and lactic acid combination in the treatment of molluscum contagiosum in children. J Dermatolog Treat. 2013 Aug;24(4):300-4. PubMed
- Rogers RS 3rd, Callen J, Wehr R, Krochmal L. Comparative efficacy of 12% ammonium lactate lotion and 5% lactic acid lotion in the treatment of moderate to severe xerosis. J Am Acad Dermatol 1989;21(4 Pt 1):714-6. PubMed
- Jennings MB, Logan L, Alfieri DM, Ross CF, Goodwin S, Lesczczynski C. A comparative study of lactic acid 10% and ammonium lactate 12% lotion in the treatment of foot xerosis. J Am Podiatr Med Assoc 2002;92(3):143-8. PubMed
- Dahl MV, Dahl AC. 12% lactate lotion for the treatment of xerosis. A double-blind clinical evaluation. Arch Dermatol 1983;119(1):27-30. DOI
- Pham HT, Exelbert L, Segal-Owens AC, Veves A. A prospective, randomized, controlled double-blind study of a moisturizer for xerosis of the feet in patients with diabetes. Ostomy Wound Manage 2002;48(5):30-6.
- Draelos ZD, Hall S, Munsick C. A 14-day Controlled Study Assessing Qualitative Improvement with 15% Lactic Acid and Ceramides in Skin Moisturization and Desquamation. J Clin Aesthet Dermatol 2020;13(8):E54-E58.
- Jennings MB, Alfieri D, Ward K, Lesczczynski C. Comparison of salicylic acid and urea versus ammonium lactate for the treatment of foot xerosis. A randomized, double-blind, clinical study. J Am Podiatr Med Assoc 1998;88(7):332-6. PubMed
- Ademola J, Frazier C, Kim SJ, Theaux C, Saudez X. Clinical evaluation of 40% urea and 12% ammonium lactate in the treatment of xerosis. Am J Clin Dermatol 2002;3(3):217-22. PubMed
- Jennings MB, Alfieri DM, Parker ER, Jackman L, Goodwin S, Lesczczynski C. A double-blind clinical trial comparing the efficacy and safety of pure lanolin versus ammonium lactate 12% cream for the treatment of moderate to severe foot xerosis. Cutis 2003;71
- Uy JJ, Joyce AM, Nelson JP, West B, Montague JR. Ammonium lactate 12% lotion versus a liposome-based moisturizing lotion for plantar xerosis. A double-blind comparison study. J Am Podiatr Med Assoc 1999;89(10):502-5. PubMed
- US Food and Drug Administration (FDA). Cosmetic Ingredients: Alpha Hydroxy Acids. August 2020. Available at: https://www.fda.gov/cosmetics/cosmetic-ingredients/alpha-hydroxy-acids. Accessed on October 19, 2021.
- Diebold R, Schopf B, Stammer H, Mendling W. Vaginal treatment with lactic acid gel delays relapses in recurrent urinary tract infections: results from an open, multicentre observational study. Arch Gynecol Obstet 2021;304(2):409-417. PubMed
- Khattar JA, Musharrafieh UM, Tamim H, Hamadeh GN. Topical zinc oxide vs. salicylic acid-lactic acid combination in the treatment of warts. Int J Dermatol 2007;46(4):427-30. PubMed
- Emtestam L, Kaaman T, Rensfeldt K. Treatment of distal subungual onychomycosis with a topical preparation of urea, propylene glycol and lactic acid: results of a 24-week, double-blind, placebo-controlled study. Mycoses 2012;55(6):532-40. PubMed
- Siskin SB, Quinlan PJ, Finkelstein MS, Marlucci M, Maglietta TG, Gibson JR. The effects of ammonium lactate 12% lotion versus no therapy in the treatment of dry skin of the heels. Int J Dermatol 1993;32(12):905-7. PubMed
- Robinson D, Friedmann D, Gordon J, Wortzman M, Nelson D. Efficacy and Tolerability of a Double-Conjugated Retinoid and Alpha Hydroxy Acid Cream in Subjects With Mild to Moderate Blemish-Prone Skin. J Drugs Dermatol 2022;21(1):54-59. DOI
This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.
Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Brands that make products with Lactic Acid
145 brands in our database make a supplement containing Lactic Acid.
Supplement products with Lactic Acid
780 products in our database contain Lactic Acid. Open any to see its full ingredient list and every drug interaction we check.
Lactic Acid: Common Questions
What is Lactic Acid used for, and does it work?
Does Lactic Acid interact with prescription medications?
How are Lactic Acid interactions rated?
Is it safe to take Lactic Acid with my medications?
Where does this Lactic Acid interaction information come from?
What is Lactic Acid used for?
Is Lactic Acid safe?
Does the Lactic Acid from exercise need a supplement to clear?
Can I use Lactic Acid products if I am pregnant?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Products that contain Lactic Acid
A rotating sample of real supplements in our database that list Lactic Acid — open any to see its full ingredients and every drug interaction we check.
- Calcium 750 mg + D 37.5 mcg (1500 IU) by Puritan's Pride
- Omega 3 + DHA by Hero Nutritionals Yummi Bears
- Omega-3 100 mg by CVS Pharmacy
- NutraDrops Quercetin by Source Naturals
- Children's Multivitamin Gummies by Equate
- NutraDrops Quercetin by Source Naturals
- CBD Gummies 15 mg by Hemp Bombs
- Omega-3 DX by Natural Dynamix
- Digestive Advantage Kids Daily Probiotic Everyday Health Superfruit Punch by Schiff
- Cheer Up & Chill Out Strawberry Gummies by Shaklee Multi-Taskers
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