Pityriasis rosacea is a common skin disease. It appears as a rash that can last from several weeks to several months. The skin rash follows a very distinctive pattern. In 3/4 of the cases, a single, isolated oval scaly patch (the herald patch) appears on the body, particularly on the trunk, upper arms, neck, or thighs. Often, the herald patch is mistaken for ringworm (tinea cruris) or eczema. Within a week or two more pink patches will occur on the body and on the arms and legs. These patches often form a pattern over the back resembling the inverted christmas tree. Patches may also appear on the neck and, rarely, on the face. These spots usually are smaller than the herald patch. The rash begins to heal after 2-4 weeks and is usually gone by 1-3 months. Rarely a skin biopsy might nail the diagnosis but it should be preceded by skin scraping for fungus.Treatment may include external and internal medications for itching. Oatmeal baths, anti-itch medicated lotions and steroid creams may be prescribed to combat the rash. Lukewarm, rather than hot, baths may be suggested. Strenuous activity, which could aggravate the rash, should be discouraged. Ultraviolet light treatments given under the supervision of a dermatologist may be helpful. Recently, both the antiviral drug Famvir and the antibiotic erythromycin have been claimed to produce healing in one to two weeks. For severe cases a few days of oral anti-inflammatory medications such as prednisone may be necessary to promote healing. For mild cases, no treatment is required as this disease is not a dangerous skin condition.
Itching and redness in groin could be ringworm infection (tinea cruris) Request your dermatologist to do a fungal scraping to confirm the fungal infection.Treatment for that would include antifungal creams such as: Terbinafin, ketoconazole, oxiconazole, clotrimazole etc. Systemic antifungals are rarely needed.