What is Nummular Dermatitis?
Nummular dermatitis is an inflammatory skin irritation that characterized by the round, coin-shaped lesions. It can be referred to as discoid eczema that affects approximately 2 in every 1000 people in U.S and is most prevalent in middle-aged patients. Men are more commonly affected by nummular dermatitis, with their first outbreak occurring between the ages of 55-65. While women affected by this condition experience their first outbreak much earlier in life, between the ages of 15 -25. It is very rare to notice this type of dermatitis in children.
What are the Symptoms of Nummular Dermatitis?
The term “nummular” derives from the Latin word for coin, and nummular dermatitis is most common for the unique coin-shaped lesions which appear on the skin at the onset of an outbreak. These discoid lesions often appear on the legs; however, it can be found on the hands, feet, torso and arms. Commonly, they start off as small red itchy and burning blisters that range in size from 1-4 inches in diameter. Then, the blisters can fill and weep fluid. As the rash reach to the end stages, your skin can become crusty, scaly, and raw. If the rash has a yellowish color, it can be signal infection.
Often, the patches begin to heal from the center of the coin shape outwards toward the edges creating a ring-like appearance. Then, your skin in-between the circular patches will be clear but it may be dry and sensitive. When the lesions are cleared, they may leave the healed skin looking darker or lighter than the surrounding skin. That discoloration will be resolved; however, if your rash has occurred beneath the knee, the changes in pigmentation may be permanent.
What’s Causing Nummular Dermatitis?
The exact cause of nummular dermatitis is still unknown. However, certain risk factors and triggers have been identified. Actually, it is not uncommon for a patient’s personal or family history to check allergies, asthma, atopic dermatitis, or similar diseases. Moreover, there are several conditions that can trigger or worsen the condition:
- Weather conditions: hot, cold, humid , or dry conditions are irritating
- Wool, or tight fitting clothing which is not cotton
- Frequent bathing
- Injury to the skin, as a burn, insect bite, or abrasion
- Bacterial skin infection
- Isotretinoin—a commonly prescribed medication for acne
- Harsh soaps, detergents or solvents.
Moreover, some researchers think that those who suffer from nummular dermatitis show a heightened sensitivity and even an allergy to some materials such as:
- Neomycin and other topical antibiotics
- Mercury: it is believed that it is a rare trigger; however, some patients recover only when all their mercury fillings are removed which leads to the belief that the reaction was because of inhaling mercury vapor.
How is Nummular Dermatitis diagnosed?
Due to the unique appearance of nummular dermatitis, the visual diagnosis can be made in most cases. If there is no doubt that a physician may do a skin biopsy to rule out any other conditions.
What Is the Treatment of Nummular Dermatitis?
The bad news that there is no cure for nummular dermatitis. The most cases, the condition is chronic and persistent. Rashes will go through phases of remission and flare-ups. Some people clear the rash within a year, while others have recurring outbreaks for many years. The rash does tend to recur at the original site of infection.
Basic treatment of nummular dermatitis is centered around preventing future flare-ups, when a flare-up does occur by treating the symptoms of the rash. Preventing flare-ups can be done via proper skin care and avoiding irritating conditions and substances. Following are some measures that you can use to treat and prevent repeat flare-ups.
- Moisturize: apply lotion to your skin after bathing and a couple of times daily.
- Protect the skin from injury.
- Avoid the activities which cause excessive sweating and overheating
- Take cool to lukewarm showers.
- Use humidifier in cold dry conditions.
- Wear loose-fitting cotton clothing.
- Use mild soaps that are fragrance-free and dye-free.
- Avoid dryer sheets and fabric softener.
- Avoid contact with harsh chemicals like petroleum products, fertilizers, or gasoline.
- Avoid extremely hot and cold weather conditions.
If a mild outbreak occurs, it can be contained and treated with non-prescription topical cortisone creams or gentle hypoallergenic lubricating creams that relieve the itching and burning. While if the outbreak is more aggressive, your doctor will recommend prescription-strength topical cortisone creams or steroidal creams, oral antihistamines, cortisone or steroids, or injectable cortisones or steroids. Regarding the outbreaks that are infected or that fail to respond to treatment, a course of oral antibiotics, topical coal tar products, and ultraviolet light therapy may be used.
The sufferers from nummular dermatitis are at increased risk of developing secondary allergic contact dermatitis which can certainly contribute to the severity of their dermatitis. After identifying triggers, you need to do patch testing to improve the quality of life in these patients.
Herbal Treatments for Nummular Dermatitis
Many all-natural herbal methods are used to help relieve the pain and itching that associated with a nummular dermatitis outbreak. There are certain herbs that have antiseptic and anti-inflammatory properties which can help to relieve the symptoms. These healing herbs include the following:
- Aloe Vera gel and the juice and leaves of the common plantain: You can apply them topically to the affected areas in order to help soothe skin irritations which associated with dermatitis.
- Calendula licorice root, and ginkgo all have antiseptic and anti-inflammatory properties. You can apply them to the form of lotions, oils or ointments to reduce the itching and inflammation.
Some experts find that the following herbal pastes can be helpful in relieving the intense itching which associated with nummular dermatitis:
- Calamine lotion
- Green clay and goldenseal root in equal parts
- Equal parts salt, water, clay, and peppermint oil
- Coal tar lotions, shampoos, and bath oils
Pyrithione Zinc Treatment
Pyrithione zinc has been recognized due to its unique skin-healing properties. Those healing properties have the ability to alleviate the itching and burning symptoms that associated with nummular dermatitis.
Pyrithione zinc is an anti-seborrheic, which means that it can help preventing or relieve excessive secretions of oil via the sebaceous glands. These glands lie beneath your skin and soften and lubricate the skin and hair. If they become overactive, the skin can become inflamed and irritated. Pyrithione zinc can limit these outbreaks and reduce flare-ups of atopic dermatitis by its ability to modulate the function of the sebaceous glands.
It also has antifungal and antibacterial properties, that can help reduce skin inflammation that associated with secondary infection in patients with dermatitis. Topical zinc pyrithione is recognized as a safe and effective treatment for reduction in the symptoms that associated with dermatitis.