Human health and medicine

Parity

Parity, in obstetrics, is the number of times a woman has given birth at a viable gestational age, counted per pregnancy: a twin birth adds one, not two.

Parker H. "Pete" Petit is an American engineer and medical-device entrepreneur, elected to the National Academy of Engineering in 2011, who developed the first home SIDS monitor and founded Healthdyne and MiMedx Group.

Parkes Weber syndrome

Parkes Weber syndrome (PKWS), a rare congenital vascular malformation disorder with limb overgrowth, port-wine stain capillary malformations, and high-flow arteriovenous fistulas; caused by RASA1 or EPHB4 variants, distinct from Klippel-Trenaunay syndrome.

Parkinson's disease

Parkinson's disease, also called shaking palsy, is the second-most common neurodegenerative disorder, defined by substantia nigra dopaminergic neuron loss and α-synuclein Lewy bodies, causing tremor, rigidity, and bradykinesia, treated with levodopa and deep brain stimulation.

Parkinsonian-pyramidal syndrome

Parkinsonian-pyramidal syndrome (pallidopyramidal syndrome, PARK15) is a rare autosomal recessive genetic disorder combining parkinsonian and pyramidal signs, mainly from FBXO7 mutations.

Parkinsonism

Parkinsonism, also called parkinsonian syndrome or Parkinson-plus when atypical, is a clinical syndrome of bradykinesia with rigidity, resting tremor, or postural instability; Parkinson's disease is its most common cause.

Parkinsonism with polyneuropathy

Parkinsonism with polyneuropathy (PKNPY, OMIM 619279, ORPHA:611237) is a rare autosomal dominant neurodegenerative disorder with levodopa-responsive tremor-dominant parkinsonism from ages 40–70 and polyneuropathy from the early twenties, linked to UQCRC1 variants.

Parkland Memorial Hospital

Parkland Memorial Hospital, Dallas County's public hospital since 1894 and flagship of Parkland Health, is a 983-bed Level I trauma center and UT Southwestern's primary teaching hospital, relocated to a new campus in 2015.

Parnacandra Rasa

Parnacandra Rasa, also spelled Purnachandra or Poornachandra Rasa, is a classical Ayurvedic herbo-mineral rasa yoga from Bhaishajya Ratnavali containing rasa sindura, abhraka, lauha, and swarnamakshika bhasmas, shilajatu, and vidanga, used as a rasayana and vajikarana tonic.

Parnaparin sodium

Parnaparin sodium (Fluxum) is a low-molecular-weight heparin from porcine intestinal mucosa, mean MW about 4.5–5 kDa, anti-Xa/anti-IIa ratio above 4, used for thromboprophylaxis, superficial vein thrombosis, and vascular disorders.

Paronychia

Paronychia, inflammation of the nail folds, acute (6 weeks, irritant dermatitis with Candida); the most common hand infection, treated by drainage, soaks, and irritant avoidance rather than routine antibiotics.

Parosmia

Parosmia (ICD-11 MB41.1) is a distorted perception of smell in the presence of an odor, common after COVID-19; distinguished from phantosmia; treated mainly with olfactory training.

Parotid gland

Parotid gland: largest of the three paired major salivary glands, in the retromandibular fossa; serous saliva via Stensen duct; facial nerve traverses it; site of 80% of salivary tumors.

Sep 29, 2026

Parotidectomy

Parotidectomy is the partial or complete surgical removal of the parotid gland, the largest salivary gland, performed mainly for tumors while preserving the facial nerve.

Parotitis

Parotitis: inflammation of the parotid salivary gland, caused by mumps and other viruses, bacterial ascending infection, stones, autoimmune disease, or drugs; mumps parotitis lasts 3–7 days, MMR is 86% effective at two doses.

Paroxetine

Paroxetine (Paxil, Seroxat) is an SSRI antidepressant first FDA-approved December 29, 1992 for depression, later for OCD, panic, social anxiety, GAD, and PTSD in adults; a potent CYP2D6 inhibitor with notable discontinuation and pregnancy cardiac-anomaly concerns.

Paroxysmal atrial fibrillation

Paroxysmal atrial fibrillation (pAF, paroxysmal AFib): self-terminating AF episodes under 7 days, about half of AF cases, driven mainly by pulmonary vein triggers, progressing to persistent AF in about a third of patients within 10 years.

Paroxysmal cold hemoglobinuria

Paroxysmal cold hemoglobinuria (PCH, Donath-Landsteiner syndrome) is a rare autoimmune hemolytic anemia caused by a biphasic IgG anti-P antibody that lyses red cells on rewarming, mainly in children after viral infection.

Paroxysmal exertion-induced dyskinesia

Paroxysmal exertion-induced dyskinesia (PED, DYT18, GLUT1 deficiency syndrome 2) is a rare autosomal dominant dyskinesia triggered by prolonged exercise, often caused by SLC2A1 mutations and treated by trigger avoidance and ketogenic diet.

Paroxysmal extreme pain disorder

Paroxysmal extreme pain disorder, formerly familial rectal pain syndrome, is a rare inherited condition causing attacks of severe pain with skin flushing due to SCN9A mutations.

Paroxysmal hemicrania

Paroxysmal hemicrania, also called chronic paroxysmal hemicrania (CPH), is a rare trigeminal autonomic cephalalgia: unilateral 2–30 minute headache attacks over 5 times daily with ipsilateral autonomic signs, absolutely responsive to indomethacin.

Paroxysmal kinesigenic dyskinesia

Paroxysmal kinesigenic dyskinesia (PKD) is a rare movement disorder with brief attacks of chorea or dystonia triggered by sudden voluntary movement. Mainly caused by PRRT2 gene mutations; responds to carbamazepine.

Paroxysmal nocturnal dyspnoea

Paroxysmal nocturnal dyspnoea (PND), also called paroxysmal nocturnal dyspnea, is sudden breathlessness waking a person from sleep, relieved by sitting up; a typical symptom of left heart failure and a Framingham major criterion.

Paroxysmal non-kinesigenic dyskinesia

Paroxysmal non-kinesigenic dyskinesia (PNKD), historically Mount-Reback syndrome, is a rare inherited neurological disorder causing dystonic attacks triggered by alcohol, caffeine, stress, or fatigue, lasting minutes to hours.

Paroxysmal supraventricular tachycardia

Paroxysmal supraventricular tachycardia (PSVT) is a regular, rapid heart rhythm of abrupt onset and termination, mostly AVNRT or AVRT; treated acutely with vagal maneuvers and adenosine, and cured by catheter ablation in 94-98% of cases.

Paroxysmal tachycardia

Paroxysmal tachycardia: abnormally rapid heartbeats with sudden onset and cessation (ICD-11 MC81.3, ICD-10 I47). Covers PSVT, mainly AVNRT; treated with vagal maneuvers, adenosine, and newly approved intranasal etripamil.

PARP inhibitor

A PARP inhibitor, also called a poly (ADP-ribose) polymerase inhibitor, blocks PARP, an enzyme that repairs damaged DNA, and is used to treat BRCA-mutated ovarian, breast, pancreatic, and prostate cancers.

Parry–Romberg syndrome

Parry–Romberg syndrome, or progressive hemifacial atrophy, is a rare autoimmune neurocutaneous disorder causing progressive unilateral facial tissue atrophy, with neurologic involvement (seizures, migraine) and overlap with linear scleroderma en coup de sabre.

Parsaclisib

Parsaclisib (INCB050465, IBI-376) is Incyte's investigational next-generation PI3Kδ inhibitor for B-cell malignancies; IC50 1 nM, 10,000-fold selective, EMA application withdrawn 2022, phase 3 myelofibrosis study failed.