Major depressive disorder
Malaria infection
Male hypogonadism
Male infertility
Malignant bowel obstruction
Malignant hyperthermia
Mantle cell lymphoma
Marfan syndrome
Marginal zone lymphoma
Median arcuate ligament syndrome
Medication overuse headache
Medication-related osteonecrosis of the jaw
Membranoproliferative glomerulonephritis
Membranous nephropathy
Ménière's disease
Meniscal tears
Menopause
Merkel cell carcinoma
Mesenteric artery aneurysm
Mesenteric vein thrombosis
Metabolic acidosis
Metabolic dysfunction-associated steatotic liver disease
Metformin toxicity
Methadone prescribing
Methemoglobinemia
Microhematuria
Microscopic colitis
Microscopic polyangiitis
Migraine
Mild cognitive impairment
Milk protein allergy
Minimal change disease
Mitral regurgitation
Mitral stenosis
Molluscum contagiosum
Monoclonal gammopathy of undetermined significance
Motion sickness
Moyamoya disease
Mpox
Müllerian agenesis
Multiple endocrine neoplasia type 1
Multiple gestation
Multiple myeloma
Multiple sclerosis
Multisystem inflammatory syndrome
Muscle cramps
Myasthenia gravis
Mycosis fungoides/Sézary syndrome
Myelodysplastic syndrome
Myelomeningocele
Myocarditis