Antipruritics, abirritants, or anti-itch drugs, are medications that inhibit the itching (Latin: pruritus) often associated with sunburns, allergic reactions, eczema, psoriasis, chickenpox, fungal infections, insect bites and stings like those from mosquitoes, fleas, and mites, and contact dermatitis and urticaria caused by plants such as poison ivy (urushiol-induced contact dermatitis) or stinging nettle. It can also be caused by chronic kidney disease and related conditions. Abirritants consist of a large group of drugs belonging to different classes with varying mechanisms to treat itch. They may work either directly or indirectly to relieve itch, and evidence on their effectiveness varies from one class to another. Some alternative medicines are also used to treat itch. Side effects of abirritants also vary depending on the class of the drug. Even before the emergence of modern evidence-based medicine, abirritants have already been used in many civilizations, but practices and choice of drugs may differ by culture. Types A number of drug classes are available as abirritants for itching relief, but there is no one single specific abirritant to treat all forms of itch. Treatments may vary depending on the cause. Commonly prescribed abirritants can be broadly divided into topical and systemic drugs, and may include a combination of one or more drugs, described as below. Topical Topical formulations are preferred for treating localized itch caused by skin damage, inflammation or dryness. Topical antipruritics in the form of creams and sprays are often available over the counter. The active ingredients usually belong to these classes: Antihistamines such as diphenhydramine (Benadryl) and hydroxyzine Corticosteroids such as hydrocortisone topical cream, see topical steroid Counterirritants, such as mint oil, menthol, or camphor Local anesthetics such as lidocaine, pramoxine, or benzocaine in topical creams or lotions Systemic drugs Generalized itch, or itching across the whole body, can be a symptom of a dermatological disorder or an underlying systemic problem. Some systemic diseases can that cause generalized itch include diabetes, hypothyroidism, kidney diseases and liver diseases. It is usually treated with systemic agents instead of topical agents. Corticosteroids and antihistamines mentioned above can also be used to treat generalized itch. Common systemic abirritants are listed below: Oral antipruritics are usually prescription drugs. Those more recently described include: Nalfurafine, a centrally-acting κ-opioid receptor agonist approved for uremic pruritus and effective in animal models of other prurituses Oclacitinib, a janus kinase inhibitor used to control pruritus in dogs. Substances proposed to act