Humalog, manufactured by drugs giant Eli Lilly, is a form of insulin that is used to help diabetics manage their condition. Specifically, Humalog is Insulin lispro, a fast acting form of insulin which was first introduced in 1996 and which has since become a preferred treatment choice in many cases due to its ability to release into the bloodstream more quickly than regular insulin.
Humalog has become the preferred form of insulin used by extreme bodybuilders who have been using insulin since the mid 1990's to take advantage of its ability to drive nutrients to muscles. This form of use is very dangerous though with some deaths being attributed to miscalculating how to use Humalog.
As a result of its faster onset time, Humalog allows users more flexibility over meal timings and less waiting around between having an injection and eating their meal. This makes it preferable to slower acting forms of insulin for many.
Humalog should only be used by diabetics, with both type 1 and type 2 diabetics being prescribed this drug.
In general, Humalog will be taken before a meal but the exact timing and dosing is something which should be established by your healthcare provider. Always refer to product literature.