Some bodybuilders, particularly at professional level, inject 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% lidocaine, and 7.5% alcohol.It is not restricted, as it is ostensibly sold for topical use only, and many brands are available on the internet.