Gynaecomastia

Question 1

What is gynaecomastia?

Answer 1

Gynaecomastia describes an abnormal amount of breast tissue in males and is usually caused by an increased oestrogen:androgen ratio.

Question 2

What is important to differentiate in relation to gynaecomastia?

Answer 2

It is important to differentiate the causes of galactorrhoea from those of gynaecomastia.

Question 3

What are physiological causes of gynaecomastia?

Answer 3

Physiological causes include normal changes during puberty.

Question 4

What syndromes are associated with androgen deficiency that can cause gynaecomastia?

Answer 4

Kallman’s syndrome and Klinefelter’s syndrome.

Question 5

What are some medical conditions that can lead to gynaecomastia?

Answer 5

Conditions include testicular failure (e.g. mumps), liver disease, testicular cancer (e.g. seminoma secreting hCG), ectopic tumour secretion, hyperthyroidism, and haemodialysis.

Question 6

What is the most common drug cause of gynaecomastia?

Answer 6

Spironolactone.

Question 7

What are some other drugs that can cause gynaecomastia?

Answer 7

Other drugs include cimetidine, digoxin, cannabis, finasteride, GnRH agonists (e.g. goserelin, buserelin), oestrogens, and anabolic steroids.

Question 8

What are some very rare drug causes of gynaecomastia?

Answer 8

Very rare drug causes include tricyclics, isoniazid, calcium channel blockers, heroin, busulfan, and methyldopa.