To answer your first question, urticaria and papular urticaria are not the same. Urticaria (or hives) is a skin reaction that produces smooth, elevated patches on the skin. These patches are usually redder or paler than the surrounding skin and cause severe itching. Urticaria is a temporary condition that may be caused by an allergy to particular foods, plants, or drugs, or by stress. On the other hand, papular urticaria is a long-term condition caused by a hypersensitive reaction to bites by a large variety of insects, including mosquitoes, fleas, and bedbugs. Your sister’s skin will show papules, which are small, solid inflammations that do not contain any pus. These papules also cause severe itching. It is important that your sister avoids scratching the papules, since that can lead to infections and other complications.
Your sister’s case is uncommon since in most cases papular urticaria starts in childhood and reduces with adolescence. However, her symptoms may still reduce in the near future. You have also mentioned that your sister has undergone steroid therapy. Please note that long-term use of steroids is not recommended because of the various side effects associated with it. While there are no proven home remedies for papular urticaria, you can try to reduce your sister’s discomfort whenever her condition re-occurs. You can use various topical lotions and natural substances to reduce the itching and provide relief from the papules. Cucumber juice has a cooling effect and can be applied to the affected areas. You could also try unflavored yogurt as a substitute for commercial calamine solutions to provide relief from the itching. Adding some turmeric powder to the yogurt will provide some level of antiseptic protection as well. Some people have also reported reduced itching by applying aloe vera gel directly on the papules. Honey is another option, though it can get somewhat messy.
In case your sister’s condition is widespread, you can advise her to take a medicated bath. Fill half a tub with hot water and add half a cup each of baking soda and cornstarch. If she soaks in this bath daily, she should experience some measure of relief. From a long-term point of view, try to reduce her exposure to insects at home by installing suitable electric traps and wire netting, or by using insect repellent sprays. Please do continue consultations with a reputed dermatologist who can provide the best advice on long-term care and treatment.