Some bodybuilders, particularly at professional level, use substances such as "site enhancement oil", commonly known as synthol, to mimic the appearance of developed muscle where it may otherwise be disproportionate or lagging. This is known as "fluffing". Synthol is 85% oil, 7.5% lidocain, and 7.5% alcohol.Use is legal and many brands are available on the internet.The use of injected oil to enhance muscle appearance had previously been used in the late 19th century before being abandoned due to health risks such as sclerosing lipogranuloma. Its use was revived more recently by bodybuilders. Use can cause pulmonary embolisms, nerve damage, infections, stroke, and the formation of oil-filled oleomas, cysts or ulcers in the muscle. Sesame oil is often used, which can cause allergic reactions such as vasculitis. An aesthetic issue is drooping of muscle under gravity. Surgical methods are also often employed to remove steroid-related gynecomastia in male bodybuilders, and breast implants in female bodybuilders who wish to retain a feminine physique, which can be compromised in terms of breast reduction by intense dieting.