Trimix at room Temp for a couple hours?

[paperboy48]

I can leave Trimix at romm temperature for a couple hours, right?

[trimix60]

Yup...sometimes when I know I am going to get lucky , I will preload an injection and just put it on the counter in the bathroom for a couple of hours....ready for action !!!! Seems that the injection feels a little better when everything is at room temp.

[ohohiakane]

Paperboy...

Leaving a whole vial out may reduce the length of time of potency. Just my guess.

Bill

[Bluewhippet]

The Division of Pharmacy of The University of Texas, M.D. Anderson Cancer Center, Houson, Texas did a scientific evaluation of the Long Term Stability of Trimix in 2004. A summary of their results is as follows:

"A three-drug injection mixture of alprostadil 12.5 microgram/mL, papaverine hydrochloride 4.5 mg/mL and phentolamine mesylate 0.125 mg/mL in bacteriostatic 0.9% sodium chloride injection was evaluated for stability at 23 deg C, 4 deg C, -20 deg C and -70 deg C. The injection remained clear and colorless in all samples throughout the study. Chemical stability testing was performed using stability-indicating high-performance liquid chromatographic analysis. Alprostadil was the least stable of the drug components at room temperature and under refrigeration. About 8% alprostadil loss occurred in five days at room temperature; under refrigeration losses of about 6% and 11% occurred after 1 and 2 months, respectively. Frozen at -20 deg C and -70 deg C, less than 5% loss of any of the drug componenets occurred in 6 months. A beyond-use date of 6 months when stored frozen at -20 deg C and 1 month when stored refrigerated at 4 deg C is appropriate for batches of the injection that have passed sterility testing. Room temperature exposure should be limited, and the vial should be returned to refrigeration as soon as possible."

This means that, since 2 of the components of Trimix (paparavine and phentolamine) are reasonably stable at normal room temperature, the only deterioration occurs in the Alprostadil (PGE1). The loss of Alprostadil is only 8% after 5 days so the loss in 2 hours would be insignificant.

It makes sense to refrigerate whenever possible to reduce the possibility of bacterial contamination.