Dosing Schedules and Routes
The dosing levels and routes for exogenously admi-nistered growth hormone were first established for pit-hGH in growth hormone deficient (GHD) patients (Jorgensen, 1991; Laursen, 2004). The initial pit-hGH regimen, three times weekly by intramuscular (IM) injection, was based on a number of factors including patient compliance and limited availability of hGH derived from cadaver pituitaries. Subsequent clinical evaluations found a very strong patient preference for subcutaneous (SC) administration. Furthermore, in-creased growth rates were observed with daily SC injections compared to the previous two to three times weekly IM injection schedule (Hansen, 2002). The abdomen, deltoid muscle, and thigh are commonly used SC injection sites. Current dosing schedules are usually daily SC injections, often self-administered with a variety of injection devices.