This is from
UpToDate Online:
DOSAGE FORMS
Infusion, as sodium [premixed iso-osmotic solution]: 1 g (50 mL); 2 g (50 mL) [contains sodium 53.8 mg/g (2.3 mEq/g)]
Injection, powder for reconstitution, as sodium: 1 g, 2 g, 10 g [contains sodium 53.8 mg/g (2.3 mEq/g)]
DOSAGE FORMS: CONCISE
Infusion [premixed iso-osmotic solution]:
Mefoxin®: 1 g (50 mL); 2 g (50 mL)
Injection, powder for reconstitution: 1 g, 2 g, 10 g
Mefoxin®: 1 g, 2 g, 10 g
GENERIC EQUIVALENT AVAILABLE — Yes: Powder for injection
ADMINISTRATION
I.M.: Inject deep I.M. into large muscle mass.
I.V.: Can be administered IVP over 3-5 minutes at a maximum concentration of 100 mg/mL or I.V. intermittent infusion over 10-60 minutes at a final concentration for I.V. administration not to exceed 40 mg/mL
Now... I don't know if the vials are specified IM only/IV only/IV or IM use so I can't comment specifically on your case, however it is documented that it can be used IM. There are accepted off-label administrations for medications if prescribed. For example, Haldol, which still says IM injection only, can be given IV and has been for decades. Frankly, I would have looked into the situation in more detail. If, like Haldol, the vials say one thing but there is established (key word is established... not just now and then, for convenience) practice for another, I would have administered IM. (Now, if the physician wrote IV, it would not be acceptable to change to IM without contacting him for a correction first.)
I'm curious how this is dealt with in your hospital. How does the medication get delivered to the nurses? Does pharmacy simply deliver the vials for the nurses to administer? If so, and if IM and IV doses come from the same vials, why hasn't anyone caught this yet? Surely SOMEONE would have seen "For IV Only" on the vials at some point, wouldn't you think?