Alpha-Hydroxy Acid (AHA) Treatments#

Alpha-hydroxy acids are a family of mild, water-soluble exfoliating acids. They are derived from natural sources - sugar cane, milk, fruit, almonds - and work on the surface of the skin to loosen dead cells and reveal smoother, brighter skin underneath.

Common AHAs you will see in skincare include:

• The smallest, fastest-penetrating AHA (derived from sugar cane) - the most studied and most active
• A gentler AHA derived from milk - good for dry or sensitive skin
• An AHA derived from bitter almonds - the largest molecule, the gentlest, useful in darker skin tones
• AHAs from grapes and citrus fruits - often blended into multi-acid products

Because AHAs are water-soluble, they work on the surface (the top layer of skin) rather than inside oily pores.

AHAs loosen the bonds that hold dead skin cells together at the surface. This does three useful things:

1. Exfoliates - dead cells shed more easily, revealing fresher skin underneath.
2. Boosts cell turnover - your skin renews itself more often, which over weeks to months helps fade dark marks and smooth fine lines.
3. Supports collagen - long-term, regular use supports collagen production in the deeper skin, which improves firmness.

AHAs are most active in slightly acidic formulas. Two products at the same labelled percentage can feel quite different depending on the formula's pH.

The big difference is where each acid works:

• AHAs are water-soluble - they exfoliate the surface and are good for dullness, fine lines, and surface dark marks.
• Beta-hydroxy acids (BHAs) are oil-soluble - they work inside pores and are good for acne, blackheads, and oily skin.

In a TeleTest cosmetic-dermatology plan, AHAs and BHAs are sometimes used together on alternating days to address both surface texture and pore congestion.

AHAs are generally well tolerated by most skin types when used carefully. A few notes:

• Oily or normal skin usually tolerates daily low-strength use (5 to 10 percent).
• Dry skin benefits from a milder AHA (such as lactic or mandelic) in a moisturizing base, used a few times a week.
• Sensitive or reactive skin should start at the lowest strength (around 5 percent), twice a week, and watch for redness or stinging. A gentler AHA is a better choice.
• Rosacea-prone skin is often not a good fit - the exfoliation can trigger flushing.

If you are not sure where you fall, your TeleTest clinician can suggest a starting point during the consultation.

A general guide for at-home use:

• 5 to 8 percent - beginner, sensitive skin, or daily use.
• 8 to 10 percent - regular users with no irritation issues.
• 15 to 20 percent - occasional weekly use, or as a short-contact peel.
• 30 percent and above - professional setting only, with someone trained to apply and neutralize the peel.

Higher is not better. A lower strength used consistently produces more reliable results than a stronger peel used aggressively.

A typical nightly routine:

1. Cleanse with a gentle cleanser.
2. Dry the skin fully - applying to damp skin can sting more.
3. Apply a thin layer of the AHA product to the face, avoiding the eye area, lips, and corners of the nose.
4. Wait one to two minutes for it to absorb.
5. Moisturize with a barrier-supporting moisturizer (look for ceramides or hyaluronic acid).
6. In the morning, always use a broad-spectrum sunscreen (SPF 30 or higher) - AHAs do increase sun sensitivity.

Start with two to three nights per week. If your skin tolerates it well after two weeks, you can build up. Most people do not need it every night.

These pair well with AHAs:

• Hyaluronic acid - layers over top to hydrate.
• Niacinamide - calms redness and supports the skin barrier; use in the morning or evening on opposite nights.
• Ceramide-based moisturizers - help offset any dryness.
• Peptides - support collagen alongside the exfoliating effect.

Layering these at the same time often causes irritation:

• Vitamin A products (OTC retinol or prescription retinoid) - alternate nights instead. A common plan is AHA two nights a week, vitamin A product the other nights.
• BHA leave-on products - alternate nights to avoid over-exfoliation.
• Benzoyl peroxide - apply at a different time of day.
• Vitamin C in a low-pH form - the acids compete; use vitamin C in the morning and AHA at night.

If you are already using several actives, ask your TeleTest clinician to map out a weekly schedule.

Realistic timing with consistent use:

• 2 to 4 weeks: skin looks brighter; texture feels smoother.
• 6 to 12 weeks: noticeable improvement in dark marks, tone, and fine lines.
• 3 to 6 months: more pronounced changes, especially for sun damage and deeper texture issues.

Results fade if you stop. AHAs work as part of an ongoing routine, not a one-time fix.

Most settle within the first two to four weeks as your skin adjusts:

• Mild tingling or stinging for a few minutes after applying
• Slight redness or flushing
• Mild dryness, peeling, or flaking
• A temporary tight feeling

To reduce these: use less often, lower the strength, or pair with a richer moisturizer. If symptoms last past four weeks, stop and contact your TeleTest clinician.

Yes. AHAs remove the outer layer of dead skin cells, which means newer skin is exposed to UV light. This makes your skin more vulnerable to sunburn and dark marks.

Daily broad-spectrum sunscreen (SPF 30 or higher) is not optional while using an AHA. Reapply every two hours when outdoors. Skipping sunscreen will undo the work the acid is doing - especially if you are treating dark marks or melasma.

Stop using your AHA and contact your TeleTest clinician if you notice:

• A burning sensation that does not settle within an hour
• Blistering, raw skin, or peeling beyond mild flaking
• New or worsening dark patches (this can mean post-inflammatory hyperpigmentation from over-exfoliation, more common in darker skin tones)
• Any rash, hives, or facial swelling

Low-strength AHAs (around 10 percent or less) are generally considered low-risk because very little is absorbed. Higher-strength leave-on products and in-clinic AHA peels are typically avoided. Always run any active skincare past your prenatal care provider and your TeleTest clinician before continuing during pregnancy.

• At-home peels are typically 10 to 30 percent strength, applied for one to five minutes, then rinsed off. They give gentle, gradual improvement and are safer to use on your own.
• In-clinic peels are usually 30 to 70 percent strength, applied by a trained professional, then neutralized at a precise time. They give a deeper effect but need recovery time (redness, peeling for several days).

If you are interested in a stronger result, an in-person skincare clinic is the right place. TeleTest's cosmetic-dermatology service covers topical plans and at-home routines - we do not perform in-clinic peels.

1. Patch-test the product on the inner forearm 24 hours in advance.
2. Cleanse and dry the face.
3. Apply a thin, even layer with clean fingers or a cotton pad.
4. Leave on for the time recommended by the product (usually 5 to 10 minutes for a first try).
5. Rinse off thoroughly with cool water.
6. Apply a gentle moisturizer.
7. Wear sunscreen every day after a peel, even if it is overcast.

Do an at-home peel no more often than once a week. If you experience burning, stinging beyond a few minutes, or visible redness that lasts more than an hour, rinse off immediately and skip the peel next week.

• The smallest AHA (from sugar cane) penetrates fastest and gives the most visible results, but also stings the most.
• A gentler AHA derived from milk works more slowly but is better tolerated and adds some hydration.
• The AHA derived from bitter almonds has the largest molecule, penetrates slowly, and is the gentlest - useful in darker skin tones where reducing the risk of new dark marks matters.
• Fruit-derived AHAs (from grapes, citrus) are often blended into multi-acid products.

Most over-the-counter AHA products use one or two of these. Your TeleTest clinician can suggest a starting AHA based on your skin type.

• Pick an AHA for dullness, fine lines, sun spots, and surface dark marks.
• Pick a BHA for acne, blackheads, and oily skin.
• For mixed concerns (uneven tone and pore congestion), you can use both on different nights - or pick a product that combines them at a lower strength.

Yes. Body skin (arms, thighs, back) is thicker and tolerates AHAs well. AHA body lotions can help with rough patches on the upper arms (keratosis pilaris), dull-looking skin on the legs, or dark marks on the body.

AHAs do not bleach hair. They affect skin cells, not pigment in the hair shaft. If you notice product running into your hairline, that should not cause colour change.

You can, but you must follow with broad-spectrum sunscreen. AHAs make the skin more sun-sensitive, so morning use without sunscreen will cause more damage than benefit. Most people use AHAs at night to avoid the issue.

Persistent stinging means either the strength is too high, the formula is too low-pH, or your skin barrier needs more support. Drop to a lower strength, use a moisturizer first ("sandwich" method), and reduce frequency to twice a week. If stinging continues, switch to a gentler AHA or pause acids and focus on barrier repair (ceramides, niacinamide, hyaluronic acid).

Carefully. Both increase sun sensitivity and both exfoliate. Most plans alternate - vitamin A product some nights, AHA on other nights, with a barrier night in between. Your TeleTest clinician can map out a weekly schedule that works.

Missing a few nights does not undo progress. Just restart at your usual frequency. If you have been off for more than a couple of weeks, drop back one step (twice a week instead of three) for a week to ease back in.

Peel pads are usually higher-strength (10 to 20 percent) and meant for occasional use - once or twice a week. AHA serums are usually lower-strength (5 to 10 percent) and meant for more frequent use. They are different ways to use the same family of ingredients.

AHAs can help with the colour and surface texture of recent (still red or pink) stretch marks and surface scars, but they will not remove deeper indented scars. Deeper scarring usually needs in-person procedures (microneedling, laser).

Look for: skin that feels smoother to the touch, dark marks that look gradually lighter at 8 to 12 weeks, makeup that sits better on the face. If you see no change after 12 weeks of consistent use plus sunscreen, talk to your TeleTest clinician about adjusting the strength or switching to a different active.

Book in-person dermatology or skincare-clinic care for:

• A peel that goes wrong (blistering, prolonged redness past a week, signs of infection)
• Deep or pitted acne scars - topical AHAs can soften surface texture but do not treat deep scarring; procedures like microneedling or laser are needed
• A skin lesion that is changing in size, colour, or shape - this needs an in-person assessment
• Persistent melasma that is not improving with combination skincare

AHAs are sold as cosmetic ingredients and are not covered under your provincial health plan. Prices vary widely:

• Drugstore cleansers and toners: budget-friendly, lower strength.
• Brand-name serums and peel kits: mid-to-high range.
• Professional in-clinic peels: per-treatment cost; usually a series is recommended.

You do not need a prescription to buy AHA skincare. A TeleTest consultation can help you decide which strength and routine match your skin and other concerns, so you spend on the right product.