SkinGuide
Do Antihistamine Tablets Help Itchy Mosquito Bites?
Small studies found relief for early bite reactions. Check what they measured, why cetirizine can still cause sleepiness, and which skin changes need assessment.
ArticlesTopic 07
Skin
Adult acne, dark patches, bumps and redness. Evidence over hype for the skin you’re in.
SkinEvidence check
Can Colloidal Oatmeal Cream Help Hand Eczema? What One Trial Tested
A six-week trial favored a 1% oatmeal cream after an initial course of steroid ointment. That treatment sequence limits what the result can promise.
SkinEvidence check
Niacinamide for Dark Underarms: The Nine-Week Trial
A 4% cream improved measured pigmentation in a small study. The response ratings and excluded diagnoses limit what a serum label can promise.
SkinEvidence check
Urea Cream for Cracked Heels: What the Comparisons Show
Trials of 25% and 40% creams do not establish that stronger is better. A diabetic heel-fissure study also separates improvement from complete healing.
SkinEvidence check
Are You Using Enough Sunscreen? What Studies Show
The SPF on the bottle is measured with a thick layer of 2 milligrams per square centimeter. In everyday life, studies find people apply about a quarter to a half of that, and protection drops fast: in a Danish test, using half the amount gave roughly the square root of the SPF. People also miss parts of the face, especially the eyelids. Here is how much to use and simple ways to close the shortfall.
SkinEvidence check
Brittle, Splitting Nails After 50: What Helps? What Studies Show
Brittle nails that split, peel and break affect up to 1 in 5 people, especially women over 50. An international review of nail experts says the first step is ruling out a cause, then moisturizing and protecting the nails, with biotin and nail lacquers as options. The trials behind those options are small. Here is what the evidence shows and when nail changes need a closer look.
SkinEvidence check
Does Niacinamide Work? What the Skin Trials Show
Niacinamide, a form of vitamin B3, is in serums for everything from wrinkles to spots to acne. In a 12-week split-face trial of 50 women aged 40 to 60, a 5% niacinamide moisturizer improved fine lines, dark spots and red blotchiness more than plain moisturizer. In an acne trial, a 4% gel did about as well as an antibiotic gel. But the key aging and pigment trials came from Procter & Gamble researchers, and a Cochrane review rated the acne evidence low quality.
SkinEvidence check
Dry, Cracked Hands From Washing? What Hand Eczema Studies Show
Hand eczema is common: across 66 studies of more than half a million people, about 1 in 7 had it at some point, and women were affected 1.5 to 2 times as often as men. Soaps, detergents and frequent wetting are the usual culprits. Two Dutch hospital trials tried to prevent it with moisturizer and habit changes, with mixed results. Here is what the studies show and a routine worth trying.
SkinExplainer
Isotretinoin With Food? Check the Formulation First
Meal instructions differ between isotretinoin products. Confirm the full name on your packet, including ABSORICA or ABSORICA LD, before changing your routine.
SkinEvidence check
Raised Welts When You Scratch? What Studies Show on Skin Writing
If a light scratch leaves a raised, itchy red line within minutes, you may have dermatographism, or skin writing. Symptomatic dermatographism affects an estimated 2% to 5% of people and is the most common form of hives triggered by a physical cause. In a survey of 91 patients, symptoms were often worse in the evening and lasted about 6 years on average. A review of 23 studies found everyday non-drowsy antihistamines worked well. Here is what to know.
SkinWhat to expect
Your Mole Biopsy Says 'Dysplastic' With Positive Margins: Do You Need More Surgery?
A biopsy report reading 'mildly or moderately dysplastic nevus, margins involved' often leads to a second, wider cut. Two large U.S. studies found that when nothing visible was left behind, careful watching was a reasonable alternative. The bigger finding: people with these moles often developed melanoma somewhere else, so regular skin checks matter most.
SkinExplainer
Back and Chest Acne: How to Use a Benzoyl Peroxide Wash
About 30% to 60% of people with acne on the face also get it on the back or chest. US dermatology guidance strongly recommends benzoyl peroxide, and for the back, dermatologists suggest leaving the wash on for two to five minutes before rinsing. Results take six to eight weeks to start showing. Here is how to use it, what to skip, and when back acne needs a dermatologist.
