Human health and medicine

Pachyonychia congenita

Pachyonychia congenita (PC), also called Jadassohn-Lewandowsky or Jackson-Lawler syndrome, is a rare autosomal dominant keratin disorder from KRT6A/B/C, KRT16, or KRT17 mutations, causing thick nails, painful plantar calluses, cysts, and oral leukokeratosis, with no cure.

PACIFIC trial (NCT02125461)

PACIFIC (NCT02125461) is AstraZeneca's phase 3 trial of consolidation durvalumab (MEDI4736) after chemoradiotherapy in unresectable stage III NSCLC; it doubled median PFS (16.8 vs 5.6 months) and established the PACIFIC regimen as standard of care.

Pacifier

Pacifier (soother, dummy): silicone or latex teat with shield and ventilation holes for infant non-nutritive sucking. Reduces SIDS risk (OR 0.39), linked to otitis media and malocclusion; AAP, AAPD, and ACM guidance conflict on timing.

Oct 20, 2026

PACIFIER trial

PACIFIER (RisoR Crest Everolimus Eluting Stent trial, NCT07098195) is a Poly Medicure-sponsored, single-arm, open-label, multicentre study of 2,000 patients in India and Italy assessing target lesion failure at 360 days for a biodegradable-polymer everolimus-eluting cobalt-chromium stent.

Pacing-induced cardiomyopathy

Pacing-induced cardiomyopathy (PICM) is left ventricular systolic dysfunction caused by chronic right ventricular pacing, affecting about 12% of pacemaker patients and presenting as heart failure.

Pack-year

Pack-year: unit of cumulative tobacco exposure, one pack (20 cigarettes) daily for one year, computed as cigarettes/day × years ÷ 20; used for lung cancer screening eligibility (USPSTF 20 pack-years, Medicare and Australia 30).

Oct 20, 2026

Packaged Hospitals

Packaged Hospitals, also called Packaged Disaster Hospitals, are complete sets of hospital equipment and supplies stored long-term to set up a general hospital in an emergency, a concept from United States Cold War civil defense planning.

Packed red blood cells

Packed red blood cells (PRBCs, red cell concentrate) are plasma-depleted red cells transfused to raise oxygen-carrying capacity; stored 1-6°C up to 42 days in additive solutions like SAGM or AS-1/3/5, or frozen with glycerol.

Paclitaxel

Paclitaxel, sold as Taxol, is a chemotherapy drug isolated from Pacific yew bark that stops cancer cell division by stabilizing microtubules; the FDA approved it for ovarian cancer in 1992.

Paclitaxel chemotherapy

Paclitaxel chemotherapy is cancer treatment with paclitaxel, a taxane drug originally isolated from the Pacific yew tree, FDA-approved in 1992 and used mainly for ovarian, breast, and lung cancers.

Paclitaxel poliglumex

Paclitaxel poliglumex (PPX, CT-2103, Xyotax, Opaxio) is an investigational water-soluble conjugate of paclitaxel with poly-L-glutamic acid, inactive until cathepsin B releases the drug in tumors; phase III NSCLC trials showed no survival advantage and its EMA application was withdrawn in 2009.

Paclitaxel regimen

A paclitaxel regimen is a chemotherapy treatment plan built around paclitaxel, a microtubule-stabilizing taxane given alone or combined with agents such as carboplatin, gemcitabine, or trastuzumab to treat ovarian, breast, lung, and pancreatic cancers.

Paclitaxel/topotecan regimen

The paclitaxel/topotecan regimen is an intravenous chemotherapy combination pairing the taxane paclitaxel with topotecan, developed for recurrent, persistent, and metastatic cervical cancer and studied in ovarian and breast tumors.

PACMAN-AMI trial

PACMAN-AMI (PCSK9 Antibody Alirocumab on Coronary Atherosclerosis in Acute Myocardial Infarction) trial: 2022 European randomized trial of 300 AMI patients showing alirocumab plus rosuvastatin regressed coronary plaque, reduced lipid core, and thickened fibrous caps.

Pacritinib

Pacritinib (VONJO), a JAK2/FLT3/IRAK1 kinase inhibitor approved by FDA in 2022 for myelofibrosis with platelets below 50 × 10^9/L, dosed 200 mg twice daily, developed through PERSIST-1, PERSIST-2, and PAC203 trials.

Oct 20, 2026

PaCUDAHL-Gé trial

PaCUDAHL-Gé (NCT02749110), a French randomized trial by University Hospital, Lille (2016–2019), tested GP-provided HPV vaginal self-sampling versus GP-suggested smear in unscreened women aged 25–65 in French Flanders, with a nested Hawthorne-effect study.

PAD_RIV_CLI study

PAD_RIV_CLI (NCT04305028) is a registered Poznan University of Medical Sciences study of rivaroxaban 2.5 mg twice daily plus aspirin versus aspirin alone on claudication distance and exercise tolerance in Fontaine II PAD; never recruited, no results posted.

Padeliporfin

Padeliporfin (WST11, Tookad, Stakel) is a palladium-bacteriochlorophyll photosensitizer for vascular-targeted photodynamic therapy of unilateral low-risk prostate cancer; EU-approved 2017, not recommended by NICE.

Padsevonil

Padsevonil (UCB0942, PSL), a UCB Pharma antiseizure drug candidate for drug-resistant focal epilepsy, dual-acting on SV2A/B/C and GABA_A benzodiazepine site; failed phase 2b/3 trials and development was discontinued in 2020.

Paediatric anaesthesia

Paediatric anaesthesia (pediatric anesthesia) is the anesthesiology subspecialty for neonates, infants, and children, defined by developmental airway, cardiovascular, and pharmacologic differences, weight-based dosing, and safety guidelines from the AAP, ESAIC, and Royal College of Anaesthetists.

Paediatric type follicular lymphoma

Paediatric type follicular lymphoma (PTFL), also called pediatric-type FL, ICD-11 2A80.4, is a rare indolent B-cell lymphoma of children and young adults, t(14;18)-negative, MAP2K1/TNFRSF14/IRF8-mutant, usually cured by excision alone.

Pafolacianine

Pafolacianine (Cytalux, OTL-38) is a folate receptor-targeted near-infrared fluorescent imaging agent injected before surgery; FDA-approved in 2021 for ovarian cancer and 2022 for lung lesion identification.

Pafuramidine

Pafuramidine (DB289, pafuramidine maleate), oral prodrug of the diamidine furamidine (DB75), was the first oral drug candidate for first-stage sleeping sickness; phase 3 efficacy matched pentamidine, but 2008 liver and kidney toxicity ended development.

Paget's disease of bone

Paget's disease of bone (osteitis deformans) is a chronic disorder of disorganized, excessive bone remodeling in older adults, often asymptomatic, linked to SQSTM1 mutations, treated with bisphosphonates such as zoledronic acid, and declining in prevalence.

Paget's disease of the breast

Paget's disease of the breast, also called Paget disease of the nipple, is a rare cancer of the nipple and areola, often with itching, redness, and crusting, that usually signals underlying breast cancer.

PAGOD syndrome

PAGOD syndrome, also called pulmonary hypoplasia-agonadism-dextrocardia-diaphragmatic hernia syndrome or Kennerknecht syndrome, is an ultra-rare neonatal malformation syndrome with lung and pulmonary artery hypoplasia, agonadism, omphalocele, diaphragmatic defect, and dextrocardia; cause unknown, fewer than a dozen cases reported.

PAH clearance

PAH clearance is a renal function test measuring how quickly the kidneys remove para-aminohippurate (PAH) from plasma, the reference standard for estimating effective renal plasma flow.

Pai syndrome

Pai syndrome (Pai Levkoff syndrome, ORPHA1993, OMIM 155145) is a rare frontonasal dysplasia with median cleft lip, midline facial/nasal polyps, and pericallosal lipoma, usually with normal neurodevelopment.

PAICS deficiency

PAICS deficiency (phosphoribosylaminoimidazole carboxylase deficiency, OMIM 619859) is a rare autosomal recessive error of de novo purine synthesis causing fatal neonatal malformations or later-onset neurodevelopmental disease.