Chemistry •
Polycyclic aromatic hydrocarbon, one of a class of chemical compounds, organic pollutants •
PAH world hypothesis, hypothesis that proposes that the use of polycyclic aromatic hydrocarbons was a means for the origin of life •
Polyallylamine hydrochloride, a polyelectrolyte used in polymer sheets •
Polyanhydrides, a class of biodegradable polymers •
Photoacid, where H indicates an H atom lost by an acid
Medicine •
Para-aminohippurate, a substance used in the measurement of blood flow in the kidneys •
PAH clearance, Para-aminohippuric acid clearance, a measurement of renal plasma flow • Paradoxical adipose hyperplasia, a potential complication of
cryolipolysis •
Phenylalanine hydroxylase, an enzyme involved in breaking down phenylalanine •
Primary alveolar hypoventilation, a condition of inadequate air movement in the lungs •
Pulmonary arterial hypertension, a condition of elevated blood pressure in the pulmonary artery == Organizations==