Embodiments provide apparatus and methods for delivering liquid form medication within the body wherein the medication is stored in solid form and then mixed with a liquid in an apparatus implanted within the body. One embodiment provides an implantable apparatus for in vivo delivery of medication comprising a housing including a reservoir, a store of solid form medication (SSM) and a pump. An SSM element is added to the reservoir along with fluid to form a medication solution comprising at least one drug. The medication solution is then delivered to a delivery site using a pumping means to pump solution from the reservoir through a delivery member such as catheter to a delivery site. Embodiments of the invention are particularly useful for delivering medication to a patient to treat a medical condition over an extended period of time without requiring the patient to take external medication.