25,729 articles
Premature adrenarche
Premature adrenarche: early adrenal androgen rise causing pubic/axillary hair, body odor, and acne before age 8 in girls or 9 in boys; benign variant of puberty, diagnosis of exclusion, distinct from central precocious puberty and NCAH.
Premature atrial contraction
Premature atrial contraction (PAC, premature atrial complex) is an early extra heartbeat arising in the atria. Occasional PACs are benign; frequent PACs (over ~500/24 h) predict atrial fibrillation, stroke, and mortality.
Premature burial
Premature burial (vivisepulture) is burial while still alive; taphophobia, its fear, swept 18th-19th century Europe, spawning safety coffins, waiting mortuaries, and death-diagnosis research, though evidence shows the claimed epidemic was largely a fable.
Premature canities
Premature canities, or premature graying of hair (ICD-11 ED73.10), is hair graying before age 20 in Caucasians and 30 in Africans, linked to genetics, oxidative stress, smoking, and B12 deficiency.
Premature closure of the arterial duct
Premature closure of the arterial duct (ductus arteriosus), ORPHA:95486, ICD-10 Q25.8: rare fetal constriction or closure of the duct without structural heart defects, usually from maternal NSAIDs, causing right heart overload, hydrops, or fetal death.
Premature ejaculation
Premature ejaculation (PE), also called early ejaculation, is a common male sexual dysfunction defined by ejaculation within about one minute of penetration (lifelong) or a bothersome drop to about three minutes (acquired), treated with dapoxetine, topical anaesthetics, or SSRIs.
Premature ovarian failure
Premature ovarian failure, now called premature or primary ovarian insufficiency (POI), is loss of ovarian activity before age 40; diagnosed by 4 months of disordered cycles with FSH above 25 IU/l, affecting about 1 to 3.5 percent of women.
Premature ventricular contraction
Ventricular premature depolarization, also called premature ventricular contraction (PVC), is an early heartbeat originating in a ventricle. Common ectopic beat; burdens above 10–15% can cause reversible PVC-induced cardiomyopathy.
Premedication
Premedication: drugs given before induction of anesthesia (preanesthetic medication) or before diagnostic procedures; began with ether/chloroform-era morphine and scopolamine, now selective; contrast-media premedication is a separate use.
Premenopausal idiopathic osteoporosis
Premenopausal idiopathic osteoporosis (ICD-11 FB83.10) is rare osteoporosis in premenopausal women: low-trauma fracture with low BMD after excluding secondary causes; heterogeneous pathogenesis, no approved treatments.
Premenstrual dysphoric disorder
Premenstrual dysphoric disorder (PMDD), formerly late luteal phase dysphoric disorder, is a severe DSM-5 cyclic mood disorder affecting about 5% of reproductive-aged women, treated first-line with SSRIs.
Premenstrual syndrome
Premenstrual syndrome (PMS): cyclic physical, psychological, and behavioral symptoms in the luteal phase, resolving at menstruation. Affects about 40% of women; severe form is PMDD. SSRIs are the best-evidenced drug treatment.
Prenatal care
Prenatal care (antenatal care) is health care during pregnancy, including screening, monitoring, and health promotion. Key facts: traditional 12-14 visit US model, WHO eight-contact guideline, ACOG 2025 tailored care, declining first-trimester initiation (75.5% in 2024).
Prenatal testing
Prenatal testing: screening (first-trimester combined, quad screen, cfDNA/NIPT) and diagnostic (CVS, amniocentesis) tests for fetal aneuploidy; cfDNA sensitivity ~99% for trisomy 21 but PPV depends on prevalence; procedure loss risk ~0.1-1%.
Prenylamine
Prenylamine (Segontin, Synadrin) was a phenylalkylamine antianginal drug marketed from 1960 by Hoechst and withdrawn in 1988 as the first QT-prolongation casualty; it helped found the calcium antagonist class.
Preoperative Care
Preoperative care: medical assessment, optimization, and preparation of patients before surgery, spanning history and examination, risk-stratified testing (NICE NG45), cardiovascular evaluation (AHA/ACC), preanesthesia standards, and prehabilitation.
Preoperative Exercise
Preoperative exercise (exercise-based prehabilitation): structured training before elective surgery to raise functional capacity. Pooled data from 99 RCTs show fewer complications (OR 0.54) and shorter stay; evidence certainty varies by surgery type.
Preoperative Period
The preoperative period spans the time before surgery, from the decision to operate until the patient enters the operating room, covering assessment, testing, and fasting.
PrEP-PP study
PrEP-PP (PrEP in Pregnancy and Postpartum) is a demonstration cohort study (NCT03902418) of 1,195 pregnant women in Cape Town, South Africa, measuring PrEP initiation, continuation, adherence, and HIV incidence through 12 months postpartum.
Preparation H
Preparation H, an American hemorrhoid treatment brand first sold in 1949 and now owned by Haleon, offers ointments, creams, suppositories, wipes, and sprays with phenylephrine, pramoxine, lidocaine, and witch hazel.
PrePARe study
PrePARe (NCT04213963) is a University of Turin prospective study measuring primary aldosteronism prevalence in resistant hypertension via saline infusion testing, and comparing organ damage, metabolic, and oxidative stress outcomes against essential resistant hypertension.
PREPARE trial (NCT03073317)
PREPARE (NCT03073317), Prematurity Reduction by Pre-eclampsia Care: a Brazilian stepped-wedge cluster-randomized trial of fullPIERS plus sFlt-1/PlGF risk stratification in 1250 women with preterm preeclampsia; it showed no statistical reduction in preterm deliveries.
PREPARED study
PREPARED study (NCT00743613), Predicting Peripheral Arterial Disease in Men With Erectile Dysfunction: completed 2005-2008 observational trial by Bruton Avenue Family Practice using SHIM and ankle-brachial index; distinct from the UK PREPARED PAD registry.
Prepatellar bursitis
Prepatellar bursitis (housemaid's knee) is inflammation of the bursa in front of the kneecap, caused mainly by kneeling occupations; about one third of cases are septic, usually Staphylococcus aureus, treated with antibiotics or bursectomy.
Prepectoral breast reconstruction
Prepectoral breast reconstruction is an implant-based technique performed after mastectomy in which the implant is placed above the pectoralis major muscle, avoiding animation deformity, muscle pain, and pectoralis dissection.
Preperitoneal repair
Preperitoneal repair is a hernia operation placing mesh in the space between the peritoneum and transversalis fascia, covering the myopectineal orifice so intra-abdominal pressure secures it.
Preprosthetic Oral Surgical Procedures
Preprosthetic oral surgical procedures are operations on the jaws' hard and soft tissues performed before dentures or implants, removing bony undercuts, excess tissue, and hyperplasias.
Prepubertal anorexia nervosa
Prepubertal anorexia nervosa, also called early-onset anorexia nervosa, is a rare eating disorder of prepubescent children, defined by onset before puberty and generally before age 13.
Presbycusis
Presbycusis, or age-related hearing loss, is progressive bilateral sensorineural hearing loss from cochlear aging, causing high-frequency loss and poor speech discrimination in noise; managed with hearing aids and cochlear implants.
Presbyopia
Presbyopia is the age-related loss of the eye's accommodative focusing power, causing blurred near vision from about age 40-45. Treated with reading glasses, multifocal contacts, miotic eye drops (pilocarpine, aceclidine/VIZZ), or surgery.