Intropin (dopamine hydrochloride) intravenous admixture compatibility, Part 3: stability with miscellaneous additives.

The compatibility of dopamine hydrochloride (Intropin) with various additives in 5% Dextrose Injection, USP, was studied. Dopamine hydrochloride stability for 24 hours in the admixture was established by colorimetric and thin-layer chromatographic procedures. Dopamine hydrochloride solutions are generally stable at an acidic pH and all admixtures produced a slightly acidic solution. Additives tested and found stable for 24 hours in the presence of Intropin included heparin sodium, lidocaine hydrochloride, neutral cephalothin sodium, oxacillin sodium and gentamicin sulfate. The chemical stability of methylprednisolone sodium succinate and hydrocortisone sodium succinate was not established. Potassium chloride, calcium chloride and calcium gluceptate may be assumed to be stable in the presence of Intropin. Above pH 5.0, the calcium gluceptate-Intropin admixture exhibited a color change indicating physical incompatibility. The pH and physical compatibility of all admixtures were established. In order to avoid a fixed combination of potent drugs, it is recommended that a "piggyback" administration set or administration into a second injection site be employed when another drug is to be administered with Intropin.