Triamcinolone acetonide concentration after filtration of the solvent agent.

PURPOSE: To determine the amount of triamcinolone acetonide and the preservative benzyl alcohol after filtration.

DESIGN

Laboratory investigation.

METHODS

The probes were prepared by two different hospital pharmacies. The probes of the first pharmacy included 20 probes with 25-mg triamcinolone acetonide, unfiltered (n = 5 probes) or filtered (n = 5), or with 4-mg triamcinolone acetonide, filtered (n = 5) or unfiltered (n = 5). The probes for the second pharmacy were filtered (n = 3) probes of 25-mg triamcinolone acetonide.

RESULTS

For the probes of the first pharmacy, triamcinolone acetonide dosages were 2.4 +/- 0.8 mg, 3.1 +/- 0.6 mg, 12.8 +/- 0.7 mg, and 23.4 +/- 2.3 mg, respectively, for the filtered 4-mg probes, unfiltered 4-mg probes, filtered 25-mg probes, and unfiltered 25-mg probes, respectively. For the second pharmacy, mean triamcinolone acetonide dosage was 23.8 +/- 0.6 mg for the 25-mg filtered probes and contained benzyl alcohol in a mean concentration of 0.0013 +/- 0.0001 mg/0.1 ml.

CONCLUSIONS

Depending on the method employed and the pharmacy, preparation of triamcinolone acetonide including filtration of the solvent agent leads to a marked inter-pharmacy variation and a relatively low intra-pharmacy variation in the reduction of triamcinolone acetonide dosage.