The treatment will depend on the reason for the growth. It may simply be a matter of losing weight or cutting down your alcohol intake. If the problem is a low testosterone level, testosterone can be given by injection or as a patch. Tamoxifen – a drug that interferes with the action of oestrogen – is used by some specialists to reduce gynaecomastia. Another possibility is danazol, a drug that promotes the effect of testosterone. Danazol can have troublesome side effects, such as weight gain, acne, muscle cramps and nausea.