Laser treatment for acne might reduce comedones, but dermabrasion and laser therapy have also been known to cause scarring.Macrocomedones (1 mm or larger) can be removed by a dermatologist using surgical instruments or cauterized with a device that uses light. The acne drug isotretinoin can cause severe flare-ups of macrocomedones, so dermatologists recommend removal before starting the drug and during treatment.Some research suggests that the common acne medications retinoids and azelaic acid are beneficial and do not cause increased pigmentation of the skin. If using a retinoid, sunscreen is recommended. Rare conditions
Favre–Racouchot syndrome occurs in sun-damaged skin and includes open and closed comedones.Nevus comedonicus or comedo nevus is a benign hamartoma (birthmark) of the pilosebaceous unit around the oil-producing gland in the skin. It has widened open hair follicles with dark keratin plugs that resemble comedones, but they are not actually comedones.Dowling–Degos disease is a genetic pigment disorder that includes comedo-like lesions and scars.Familial dyskeratotic comedones are a rare autosomal-dominant genetic condition, with keratotic (tough) papules and comedo-like lesions. References
External links

Rines, George Edwin, ed. (1920). "Comedones" . Encyclopedia Americana. What causes blackheads, Treatment and Prevention Archived 2020-01-27 at the Wayback Machine
The medical literature of the decade contains hundreds of reports of small trials of GH use in nearly every type of growth failure and shortness imaginable. In most cases, the growth responses were modest. For conditions with a large enough potential market, more rigorous trials were sponsored by pharmaceutical companies that were making growth hormone to achieve approval to market for those specific indications. Turner syndrome and chronic kidney failure were the first of these “nonGH-deficient causes of shortness” to receive FDA approval for GH treatment, and Prader-Willi syndrome and intrauterine growth retardation followed. Similar expansion of use occurred in Europe.One obvious potential market was adult GH deficiency. By the mid-1990s, several GH companies had sponsored or publicized research into the quality of life of adults with severe GH deficiency. Most were people having been treated with GH in childhood for severe deficiency. Although the injections are painless, many of them had been happy to leave injections behind as they reached final heights in the low-normal range. However, as adults in their 30s and 40s, these people, who had been children with growth hormone deficiency, were now adults with growth hormone deficiency and had more than their share of common adult problems: reduced physical, mental, and social energy, excess adipose and diminished muscle, diminished libido, poor bone density, higher cholesterol levels, and higher rates of cardiovascular disease. Research trials soon confirmed that a few months of GH could improve nearly all of these parameters. However, despite marketing efforts, most GH-deficient adults remain untreated.