Hydroxychloroquine, sold under the brand name Plaquenil among others, is a medication used to prevent and treat malaria in areas where malaria remains sensitive to chloroquine. Other uses include treatment of rheumatoid arthritis, lupus, and porphyria cutanea tarda. It is taken by mouth, often in the form of hydroxychloroquine sulfate.Common side effects may include vomiting, headache, changes in vision, and muscle weakness. Severe side effects may include allergic reactions, vision problems, and heart problems. Although all risk cannot be excluded, it remains a treatment for rheumatic disease during pregnancy. Hydroxychloroquine is in the antimalarial and 4-aminoquinoline families of medication.Hydroxychloroquine was approved for medical use in the United States in 1955. It is on the World Health Organizations List of Essential Medicines. In 2019, it was the 122nd most commonly prescribed medication in the United States, with more than 5 million prescriptions.Hydroxychloroquine has been studied for an ability to prevent and treat coronavirus disease 2019 (COVID-19), but clinical trials found it ineffective for this purpose and a possible risk of dangerous side effects. Among studies that deemed hydroxychloroquine intake to cause harmful side effects, a publication by The Lancet was retracted due to data flaws. The speculative use of hydroxychloroquine for COVID-19 threatens its availability for people with established indications. Medical uses
Hydroxychloroquine treats rheumatic disorders such as systemic lupus erythematosus, rheumatoid arthritis, and porphyria cutanea tarda, and certain infections such as Q fever and certain types of malaria. It is considered the first-line treatment for systemic lupus erythematosus.
Halo nevus (also known as "Leukoderma acquisitum centrifugum," "Perinevoid vitiligo," and "Sutton nevus": 689 ) is a mole that is surrounded by a depigmented ring or halo. Presentation
Halo nevi are also known as Suttons nevi, or leukoderma acquisitum centrifugum. Halo nevi are named such because they are a mole (nevus) that is surrounded by an area of depigmentation that resembles a halo. Halo nevi are associated with vitiligo. Sometimes the pale (hypopigmented) areas will spontaneously regress, and pigment returns. Causes
The formation of a halo surrounding a nevi is believed to occur when certain white blood cells called CD8+ T lymphocytes destroy the pigment-producing cells of the skin (melanocytes). The cause for the attack is unknown. Diagnosis
Treatment
As halo nevi are only of cosmetic significance, no treatment is required, and patients will be asymptomatic. Although halo nevi are harmless, it is important to monitor the lesion on regular basis. Watch out for any changes in appearance of existing or new halo nevi. If there is any change in appearance or is associated with pain, itch, and infection, a doctor should be consulted immediately to exclude the possibility of melanoma. Epidemiology
Halo nevi are estimated to be present in approximately 1% of the general population, and are found to be more prevalent in people with vitiligo, malignant melanoma, or Turner syndrome. All races and sexes are equally susceptible to this disease, although a familial tendency has been reported. The average age of onset is in a persons teenage years. See also
Nevus
List of cutaneous conditions

References


== External links ==