In most cases, a single, 2 to 10 cm (1" to 4") oval red "herald" patch appears, classically on the trunk or neck, having an appearance similar to ringworm. Occasionally, the herald patch may occur in a hidden position (in the armpit, for example) and not be noticed immediately. The herald patch may also appear as a cluster of smaller oval spots, and be mistaken for acne. Rarely, it does not become present at all. After the herald patch appears, usually some days or weeks later, a rash of many small (5–10 mm; 1⁄4" to 1⁄2") pink or red, flaky, oval or round spots appear. They are mostly situated on the trunk and upper limbs. They follow the skins cleavage lines, which on the upper chest and back produce a characteristic "christmas-tree" distribution. In 6% of cases an "inverse" distribution may occur, with rash mostly on the extremities. In children, presentation can be atypical or inverse, and the course is typically milder. About one in four people with PR have mild to severe symptomatic itching. (Moderate itching due to skin over-dryness is much more common, especially if soap is used to cleanse the affected areas.) The itching is often non-specific, and worsens if scratched. This tends to fade as the rash develops and does not usually last through the entire course of the disease.About a fifth of cases have an atypical form, with significant variations in symptoms including the size, distribution, morphology, and evolution of the lesions.
Alcohol intolerance  is due to a genetic polymorphism of the enzyme alcohol dehydrogenase, the enzyme that metabolises ingested alcohol. This polymorphism is most often reported in Asian patients. It can also be an effect or side effect associated with certain drugs such as disulfiram, metronidazole, or nilutamide. Stuffy nose and skin flushing are the most common symptoms when ingesting alcohol. It may also be characterized as intolerance causing hangover symptoms similar to the "disulfiram-like reaction" of aldehyde dehydrogenase deficiency or chronic fatigue syndrome. Severe pain after drinking alcohol may indicate a more serious condition.If people are intolerant, some non-alcoholic beverages may be a problem, similar to alcohol-containing medications, vinegar, inhalation of alcohol or the vapour of alcohol-containing cleaning agents.Drinking alcohol first or afterwards together with calcium cyanamide, an inorganic compound used as a fertilizer, can cause permanent or long lasting intolerance (nitrolime disease), contributing  together with other substances to the accumulation of harmful acetaldehyde by inhibiting the enzyme acetaldehyde dehydrogenase. See also
Disulfiram-like drug
Alcohol flush reaction


== References ==