A ganglion cyst is a fluid-filled swelling that develops near a joint or tendon. The cyst can range from the size of a pea to the size of a golf ball.
Find out about gastritis, including what the symptoms are, why it happens and how it's treated.
Find out about gastroparesis, including what the symptoms are, what the treatments are, how it's diagnosed, and what causes it.
Find out about general anaesthesia, which is used during surgery to make you unconscious so you will not know what is happening or feel any pain.
Read about Gilbert's syndrome, a genetic hereditary disorder where slightly higher than normal levels of bilirubin build up in the blood, causing jaundice.
Glutaric aciduria type 1 (GA1) is a rare but serious inherited condition. It means the body can’t process certain amino acids, causing a harmful build-up of substances in the blood and urine.
Find out about granuloma annulare, including the symptoms, treatments and causes.
Find out about granulomatosis with polyangiitis (GPA), including what the symptoms are, how it's diagnosed and how it's treated.
Find out about growing pains, what the symptoms are, how you can treat it, when to get medical help, and what the causes are.
Read about gallbladder removal surgery (cholecystectomy), including why it's done, what's involved and what the potential risks are.
Gallstones are small stones, usually made of cholesterol, that form in the gallbladder. They do not usually cause any symptoms and do not need to be treated.
Gangrene is a serious condition in which a loss of blood supply causes tissue to die. It can affect any part of the body but typically starts in the toes, feet, fingers and hands.
Read about gastrectomy, a medical procedure that involves surgically removing all or part of the stomach. Find out how it is performed, the recovery and complications from having it.
Find out what a gastroscopy is, why it's done, what happens on the day and what the results mean.
Gender dysphoria is a term that describes a sense of unease that a person may have because of a mismatch between their biological sex and their gender identity.
Genital herpes is caused by the herpes simplex virus (HSV) type 1 or type 2. It causes painful blisters to appear on the genitals and the surrounding areas.
Find out about genital warts, which are small lumps or cauliflower-like growths around the vagina, penis or anus.
Find out what gestational diabetes is, what problems it can cause, how it's diagnosed, and what the treatments are.
Find out about giardiasis, an infection of the digestive system caused by tiny parasites called Giardia intestinalis.
Find out about glandular fever including what the symptoms are, how to treat it yourself, how to stop it spreading, and when to get medical help.
Find out what glaucoma is, what the symptoms are, why it happens and how it's treated.
Read about glomerulonephritis, which is damage to the tiny filters inside your kidneys (the glomeruli).
Find out what glue ear is, what causes it, what a GP can do to help, and how it's treated.
Find out about goitre, what the symptoms are, what to do if you think you have it, how it is treated and what causes it.
Gonorrhoea is a sexually transmitted infection (STI) caused by bacteria called Neisseria gonorrhoeae or gonococcus. It used to be known as "the clap".
Find out more about gout, a type of arthritis, including the symptoms, causes, when to get help and treatments.
Find out about Guillain-Barré syndrome, including its symptoms, how it's treated, how long it takes to recover and when to get medical help.
Find out more about gum disease, including what the symptoms are, how it's treated and how to prevent it.
Find out about group B strep, a type of bacteria called streptococcal bacteria, and how it can affect you and your baby in pregnancy.
Find out about genetic and genomic testing on the NHS including how it works, when it's available, what the results can show and how genetic counselling can help.
Understand more about gallbladder cancer, its symptoms, when to get medical help, testing and diagnosis, treatment and where to find help and support.
Find out about gynaecomastia including what the symptoms are, when to get medical help, what causes it and how it's treated.
Find out about generalised anxiety disorder (GAD) including the symptoms, causes, how it's diagnosed and the treatment and support available.