Webster Dictionary(0.00 / 0 votes)Rate this definition: Melanin(noun) a black pigment found in the pigment-bearing cells of the skin (particularly in the skin of the negro), in the epithelial cells of the external layer of the retina (then called fuscin), in the outer layer of the choroid, and elsewhere. It is supposed to be derived from the decomposition of hemoglobin.
How to prepare your insulin dose if you are using two types of insulin: 1  When you mix regular insulin with another type of insulin, always draw the regular insulin into the syringe first. When you mix two types of insulins other than regular insulin, it does not matter in what order you draw them into the syringe.
Some insulin pens contain a cartridge of insulin that is inserted into the pen and some are pre-filled with insulin and discarded after all the insulin has been used. The insulin dose is dialed on the pen, and the insulin is injected through a needle, much like using a syringe. Cartridges and pre-filled insulin pens only contain one type of insulin. Two injections must be given with an insulin pen if using two types of insulin.