Skin blemishes can be caused by prolonged sun exposure to the sun or hormonal changes that occur during pregnancy. They can also be a symptom of a health condition, like an allergy, diabetes, abnormal melanocyte production, vitiligo, or a fungal infection.

Skin blemishes tend to appear to be triggered by increase melanin production by melanocytes, leading to visible dark spots on the skin.

It is important for the underlying cause of any skin blemishes to be properly identified by a dermatologist, as this will guide the most appropriate treatment approach. Treatment is aimed at lightening the blemish and preventing it from worsening, and many times, can be achieved with daily sunscreen use and lightening creams.

Why do I have blemishes on my skin?

Skin blemishes can appear for a variety of reasons. Learn about the most common conditions for blemishes below:

1. Hormonal changes

Some homronal changes, which can happen with pregnancy or menoapuse for example, can lead to the appearance of skin blemishes. These are often seen on the cheekbones and forehead, and are also referred to as melasma. Hormones can actually irritate melanocytes, resulting in darker areas on certain parts of the face. These usually appear or worsen with sun exposure.

Treatment: Apply a high-SPF sunscreen daily and avoid prolonged sun exposure, as well as heat sources. Avoid getting into hot cars parked in the sun or exposing the face to heat from the oven, for example. In addition, a cream or ointment may be used to lighten the skin. Hydroquinone may be indicated but should not be used for more than 4 weeks. Other options include tretinoin creams, cream with acids like tranexamic acid or retinoic acid.

2. Prolonged sun exposure

Sun blemishes can occur in both light or dark-skinned people, and frequently occur following unprotected over-exposure in the sun. The most affected parts of the body are the hands, arms, face and neck. Sun blemishes more commonly appear after the age of 40, although they may also occur in younger people.

Treatment: the lightest and most superficial blemishes can be eliminated by exfoliating every 2 weeks. When there is a greater number of blemishes, it is recommended that you go to the dermatologist for a prescribed treatment plan. Assessment by a dermatologist is especially significant if you have many blemishes, as you may be at a higher risk for skin cancer and evaluation is important. The use of whitening creams may be a good option but aesthetic treatments like laser, pulsed light and peeling also have great results.

3. Allergies

An allergic reaction can often cause dermatitis, which is characterized by red or brown blemishes on the skin that itch. Allergy-related blemishes may appear after the consumption of certain food (e.g. shrimp, strawberries or peanuts), after applying products to the skin (e.g. such as creams, perfumes or make-up), or after the skin comes in contact with certain objects (e.g. jewelry or watches). Learn about other common causes of red spots on the skin.

Treatment: a steroid-based cream may be indicated and should be used twice daily until symptoms subside. It is recommended that you consult a dermatologist to formally identify the underlying cause, so that in the future you can avoid whatever triggered the allergy.

4. Pityriasis versicolor

White spots on the skin, also known as pityriasis versicolor, arise due to a fungal infection. It is characterized by the appearance of several small, whitish spots on the skin that spread over time. Although the infection is not necessarily picked up at a beach, it ix often observed after a day in the sun, as the whitish skin will not tan.

The condition is caused by an overgrowth of natural fungus that is found on the skin. This proliferation of fungal cells will often occur when the person's immune system is compromised, causing scattered white spots.

Treatment: in this case, it is recommended that you apply an antifungal cream to the skin, 2 times a day for 3 weeks. When the area that needs treatment is very large, involving the entire back for example, an oral antifungal, such as fluconazole, may be required for treatment.

5. Lemon rashes

Phytophotodermatitis is the medical term for skin lesions that can be caused by lemon acid. A burn-like rash can appear after the skin comes in contact with lemon juice and is followed by sun exposure. The skin reacts and a burn or small dark blemishes in the skin can appear. It is particularly common on the hands.

Treatment: it is recommended that you wash the skin thoroughly after handling lemons. You can apply a cream with hydroquinone 3 to 4 times a day, and avoid using other skin products, such as perfumes or cosmetics, on affected skin. It is also important to always wear sunscreen on the affected area for effective treatment.

6. Diabetes rash

Acanthosis nigricans is the scientific name for dark blemishes that can appear around the neck, skin folds, underarms and under the breasts in people who have insulin resistance or diabetes. However, although it is rarer, this type may also occur in people with cancer.

How to remove: you should consult a dermatologist, who may prescribe whitening creams and identify the cause of acanthosis nigricans. Weight loss may help to reduce these blemishes and enhance treatment in those with insulin resistance.

7. Vitiligo

Vitiligo is a disease that leads to the appearance of white patches on the skin, especially in places such as the genitals, elbows, knees, face, feet and hands. Vitiligo can appear at any age. Its causes are not yet well known. Learn about other causes of white spots on the skin.

Treatment: It is recommended that you consult a dermatologist to begin appropriate treatment according to each case. Creams that even the skin tone can be used, but the use of sunscreen is essential because fair skin is more likely to develop skin cancer.

8. Acne-related blemishes

Scarring from acne is a very common cause of skin blemishes in young teens. Scarring can occur with poor skin care routines or after very severe acne treatment

Treatment: a good treatment to even-out skin tone is to apply rosehip oil directly on the scar, 2 to 3 times a day and avoiding exposure to the sun. In addition, it is also important to keep skin oil controlled with anti-acne treatments. When the person no longer has any active blackheads or pimples, treatments to lighten the skin may be prescribed, such as acid-based creams or peels, micro needling and aesthetic treatments like laser or pulsed light.

Read more about how to get rid of acne scars using cosmetic and natural interventions.

9. COVID-19

A COVID-19 infection can lead to the appearance of red or purple spots of varying sizes on the skin due to inflammation of the skin. These can be noted on the hands, soles of the feet, legs, arms, or torso in some cases. Skin blemishes from COVID-19 can appear a few weeks after the first signs of typical symptoms, like body aches, headache, fever, sore throat and general malaise, for example.

Treatment: Skin blemishes from COVID-19 usually resolve within a few weeks without the need for any treatment. However, if they are causing discomfort or itching, you are advised to consult a dermatologist. The doctor may consider prescribing topical medications to relieve discomfort and reduce inflammation.

How to remove birthmarks

Birthmarks may be reddish or darker than the skin tone, and generally do not respond well to any type of treatment, as they are a physical skin trait. However, if they cause a lot of discomfort or if visibly unpleasant, you can have the birthmark assessed by a dermatologist to evaluate which treatments are most appropriate. Treatment will depend on the location, size and the depth of each blemish.

Acid peels (which remove the superficial and middle layers of the skin) and laser treatments may be options to remove this type of blemish. Getting a tattoo and taking advantage of the shape and location of the spot can also be a positive way of coping with an unwanted birthmark.

Considerations for increasing treatment effectiveness

Some considerations for preventing new blemishes on the skin, and to prevent those that already exist from worsening are:

Always wear a sunscreen with high SPF before leaving the house;
Moisturize your body and face skin daily with creams suitable for each type;
Avoid excessive sun exposure;
Do not squeeze pimples or blackheads, which can leave dark blemishes on the skin.

These measures should also be followed when actively treating a skin blemish.