Human health and medicine

Absence seizures, atypical

Atypical absence seizures are generalized absence seizures with gradual onset and offset, pronounced tone changes, and slow irregular spike-and-wave EEG activity, typically in Lennox–Gastaut syndrome.

Absence status epilepticus

Absence status epilepticus (ASE, petit mal status) is a nonconvulsive status epilepticus: a generalized absence seizure over 30 minutes to days causing confusion, with 2.5-4 Hz spike-wave EEG, treated with low-dose benzodiazepines.

Absent bowel sounds

Absent bowel sounds (absent peristalsis, ICD-11 ME03.1): no intestinal sounds heard on abdominal auscultation, associated with ileus, bowel obstruction, ischemia, and peritonitis; diagnostic accuracy of auscultation is low.

Absent nipple

Absent nipple (athelia, ICD-11 LB61, ICD-10 Q83.2) is the congenital absence of the nipple, usually part of a syndrome such as Poland syndrome or ectodermal dysplasia, and may accompany absent breast tissue (amastia).

Oct 20, 2026

ABSORB B trial

ABSORB Cohort B trial: single-arm imaging study of the Abbott Absorb bioresorbable vascular scaffold in 101 patients at 12 European and Asia-Pacific sites, showing vasomotion return, late lumen enlargement, and no scaffold thrombosis through 2 years.

Absorbable Gelatin Sponge

The absorbable gelatin sponge is a sterile gelatin surgical sponge, best known by the brand Gelfoam from the 1940s, applied topically to control surgical bleeding when pressure or ligature fails.

Absorbable Implants

Absorbable implants, also called bioabsorbable or resorbable implants, are devices made of polymers like PGA, PLA, or magnesium that degrade in the body, avoiding hardware removal surgery; pooled RCT data show complication rates similar to metal implants.

Absorptiometry

Absorptiometry is a family of diagnostic imaging methods that measure bone mineral density by passing X-rays or gamma-ray photons through the body, used to diagnose and monitor osteoporosis.

Abulia

Abulia (aboulia), ICD-11 MG43.2, is a neuropsychiatric state of poverty of behavior and speech, lack of initiative, and reduced emotional response, caused by frontal-subcortical dopaminergic circuit dysfunction, intermediate between apathy and akinetic mutism.

Abuse-Deterrent Formulations

Abuse-deterrent formulations (ADFs) are opioid drug designs that resist crushing, extraction, or injection to deter misuse. FDA approved 10 brand-name ADF opioids 2010-2017; evidence shows reduced abuse of specific products but substitution to heroin and other opioids.

ABVD

ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) is the standard chemotherapy combination for Hodgkin lymphoma, developed by Gianni Bonadonna in 1975, given in 28-day cycles, and compared against escalated BEACOPP and newer immunotherapy regimens.

ACACIA trial

ACACIA (Adjuvant Chemotherapy for Adrenocortical CarcInomA), EudraCT 2018-000580-90, NCT03723941: Italian phase III trial of adjuvant cisplatin-etoposide with or without mitotane versus observation or mitotane in high-risk localized adrenocortical carcinoma; distinct from the ACACIA-HCM aficamten cardiology trial.

Academic detailing

Academic detailing is educational outreach in which trained professionals, usually pharmacists or physicians, visit clinicians to deliver evidence-based messages that change prescribing, modeled on pharmaceutical sales visits.

Academy of Medicine

Academy of Medicine, Singapore (AMS), professional body of medical and dental specialists founded 1957; awards FAMS, administers in-training examinations for 23 residency programs, publishes the Annals, and has 13 Colleges and 6 Chapters.

Oct 20, 2026

Acadesine

Acadesine (AICA-riboside, AICAr) is a purine nucleoside AMPK activator and adenosine-regulating agent; developed for CABG cardioprotection, failed phase 3 RED-CABG, orphan-designated for CLL and myeloma.

Acalabrutinib

Acalabrutinib (Calquence, AstraZeneca; ACP-196) is a second-generation covalent Bruton tyrosine kinase inhibitor binding Cys481, dosed 100 mg twice daily, approved for MCL and CLL/SLL, with venetoclax combination approved February 2026.

Acalabrutinib–venetoclax regimen

The acalabrutinib–venetoclax regimen is an all-oral, chemotherapy-free combination of a BTK inhibitor and a BCL-2 inhibitor for previously untreated chronic lymphocytic leukemia, FDA-approved in 2026 after the phase 3 AMPLIFY trial.

Acalculia

Acalculia (ICD-11 MB4B.2) is the acquired loss of calculation ability after stroke, brain injury, or degenerative disease, distinct from developmental dyscalculia; coined by Henschen 1920, a Gerstmann syndrome symptom, classified as primary (anarithmetia) or secondary forms.

Acalvaria

Acalvaria is a rare congenital malformation in which the bones of the skull vault and scalp muscles are absent, though the brain and face are intact.

Acamprosate

Acamprosate (Campral), the calcium salt of N-acetylhomotaurine, is an NMDA-modulating drug for maintaining abstinence in alcohol use disorder; FDA approved 2004, WHO Essential Medicines List 2023, modest efficacy versus placebo, comparable to naltrexone.

Acanthamoebiasis

Acanthamoebiasis (ICD-11 1F50) is infection by free-living Acanthamoeba amebae, causing contact-lens-associated keratitis in healthy people and often-fatal granulomatous amebic encephalitis, skin, sinus, and disseminated infections in the immunocompromised.

Acanthocyte

An acanthocyte, also called a spur cell, is an abnormal red blood cell with a few irregular thorn-like projections, found in severe liver disease, abetalipoproteinemia, and neuroacanthocytosis.

Acanthosis nigricans

Acanthosis nigricans (AN, pseudoacanthosis nigricans) is velvety dark thickening of skin in flexures, usually a marker of insulin resistance and obesity; rarely paraneoplastic (malignant AN, gastric carcinoma in 55.5% of cases).

Acariasis

Infestation by mites (acariasis, ICD-11 1G07): infestation with Acari mites, covering scabies (Sarcoptes scabiei), Demodex follicle mites, dust mite allergy, and zoonotic mite dermatitis, with diagnosis and treatment.

Acatalasemia

Acatalasemia (acatalasia, Takahara disease, catalase deficiency) is a rare autosomal recessive CAT-gene disorder with under 10% of normal blood catalase; usually asymptomatic, linked to oral gangrene and type 2 diabetes.

ACCELAMI2C19 trial

ACCELAMI2C19 (NCT00915733), also called ACCEL-AMI-2C19, was a Korean randomized pharmacodynamic trial in 126 post-PCI acute myocardial infarction patients comparing cilostazol-added triple antiplatelet therapy with 150 mg/day clopidogrel by CYP2C19 genotype.

ACCELERATE study

ACCELERATE (NCT02817997) is an international, patient-powered natural history registry for Castleman disease, launched in 2016 by the University of Pennsylvania and the Castleman Disease Collaborative Network, distinct from the pediatric oncology platform of the same name.