A rash is a noticeable change in the texture or colour of your skin. It usually involves itchy, dry skin or a rash on swollen, reddened skin. This change commonly occurs when the skin is inflamed, as seen during eczema and reactions to drugs, soaps or cosmetics. With darker skin colour it is common to observe skin texture change more commonly than skin colour change.
Signs and symptoms that may be associated with rashes include the following:
- Blister formation.
- Skin ulceration.
- Skin discolouration.
- Bumps on skin.
- With eczema, you are more likely to have symptoms like dry, scaly skin that is itchy. It may appear darker and more swollen than the surrounding skin.
- Granuloma annulare shows up with dark, circular-shaped rashes that stay for 3 weeks or more.
- In some people, there are thick collections of rashes, angular shaped and darker than surrounding skin. Commonly appearing along sweat lines (inner wrist, back and neck) called lichen planus.
There are several potential causes of skin rashes, including allergies, diseases, reactions and medications. They can also be caused by bacterial, fungal, viral or parasitic infections.
Common causes can include;
- Dyes in clothes or detergents left after washing.
- Beauty products and cosmetics.
- Poisonous plants, such as African poison ivy or velvet bean.
- Chemicals, such as latex or rubber.
- Hot and humid weather.
- Excess sun exposure.
- Scratchy clothes that don't fit properly.
Common risk factors for rashes include:
- Skin rash can occur at any age. Children who have allergies may have eczema breakouts in infancy.
- People who have a personal or family history of eczema, allergies or asthma are more likely to develop eczema.
- If you are exposed to frequent contact with metals (e.g. metal works), cleaning solvents (e.g. cleaners) or other chemicals (e.g. factory workers and agriculture product processing like cashew nuts).
- Healthcare workers.
- Health conditions that put you at increased risk of skin reactions include congestive heart failure and HIV/AIDS.
See your doctor if:
- You are so uncomfortable that you are losing sleep or are distracted from your daily routines due to the discomfort.
- You suspect your skin is infected.
- You've tried self-care steps but your signs and symptoms persist.
You can avoid some of the causes of skin rashes, including harsh detergents, cosmetics and chemicals. Rinse washed clothing until the water is clear, avoid using strong detergents or those with colouring chemicals, use mild cosmetics, moisturize your skin before going under the sun and wear protective clothing when you walk in a bushy path or under the sun.
Infections and medicines may cause a rash that you can't prevent. If you notice these reactions, report them to your healthcare provider.
Most rashes are not dangerous. Many rashes last a while and get better on their own.
- Avoiding known irritants is the most effective way to prevent rashes.
- Taking cool baths and wearing light clothing (e.g. cotton) may relieve the discomfort of rashes and soothe your skin.
- Avoid scratching the rashes excessively. Trim your nails to reduce skin breaks.
- Choose mild, unscented bath soaps (like unscented black soap). Because your clothes, sheets and towels touch your skin, choose mild, unscented laundry products when washing them.
- Manage your stress. Emotional stress can cause some types of rashes to flare up. Consider trying stress management techniques.
- Moisturizing lotions and creams (free of fragrances) promote healing and bring relief from itching.
- Use non-prescription anti-inflammation and anti-itch products. Over-the-counter (OTC) hydrocortisone cream can temporarily relieve redness and itching. Oral antihistamines, such as diphenhydramine, may help reduce itching.
- Prescription drugs that are applied to the affected skin area can change how the body reacts to allergens (topical immune modulators, e.g. tacrolimus) and can prevent or relieve moderate to severe reactions and rashes.
- Your healthcare provider may also recommend an injection to change how your body reacts to allergens (monoclonal antibodies, e.g. dupilumab) when it covers a considerable part of your body.
- In people with infected skin, your healthcare provider may recommend antimicrobial medicines to treat the infection.
- High-strength antihistamines (tablets or injections) can be prescribed for relief of swelling and serious itching.
Rashes are not life-threatening and usually go away within a week to several weeks, depending on the cause. They may, however, cause significant discomfort due to itching and can be embarrassing if it appears on the skin's prominent parts, like the face and hands.
You can identify allergens by keeping a record of when and where you experience rashes and sharing this with your healthcare provider. They will advise you on avoiding triggers if your rash is related to allergies. Self-care is an important part of managing rashes.
Some rashes are not curable, like lichen planus, and do not require treatment. You can use cosmetics to cover the appearance of the rash or wear cotton clothing over the area.