I thought Oramorph was 5ml = 10mg? But either way, yeah, depending on what dose you were wanting you use, it would probably require a larger than normal syringe. The more pressing issue is whether or not injecting Oramorph would be reasonably safe. In addition to morphine sulphate, Oramorph contains 10% ethanol (alcohol), a lot of sucrose, corn syrup, water, and the preservatives methyl parahydroxybenzoate and propyl parahydroxybenzoate. Let's go through each ingredient:
ethanol (alcohol) - The big risk with injecting ethanol is overdose, which can happen much more easily than with drinking. It might burn and be bad for veins as well.
sucrose - Sucrose is never normally injected in a medical setting. The reason is that sucrose is a disaccharide; 2 monosaccharides joined together (glucose + fructose), and since a disaccharide normally never reaches our bloodstream without being degraded into two monosaccharides first, our cells are unprepared for it and there is no mechanism to get the sucrose inside the cell. As to whether it poses any dangers to inject it, I really have no idea.
corn syrup - This one (and the ethanol) is probably the one I am most concerned about. I worry that injecting corn syrup could possibly thicken the blood, clog veins/arteries, or cause insulin imbalances.
methyl parahydroxybenzoate - Sources say that methyl parahydroxybenzoate is considered non-toxic to inject, but it is normally present in medications meant for injection in very small amounts. Larger amounts might cause side effects such as pain, but I have no idea how much of it is Oramorph. There is also the risk of an allergic reaction.
propyl parahydroxybenzoate - As with methyl parahydroxybenzoate, this one is also found in injectable solutions and is considered generally safe for injection in small amounts, but there is the risk of an allergic reaction.
TLDR: I wouldn't risk injecting this stuff, it's not worth the risks.
