It was just ten years ago that we began to use isoflurophate (DFP; Floropryl) in strabismus cases. We are indebted to S. V. Abraham1,2 for giving us the courage to try this drug after we had been dissatisfied with pilocarpine. After experimenting with various dilutions, we settled on 0.025% as the most practical (that was the weakest dilution that the manufacturer considered stable enough to put on the market in ointment form), and when we found a druggist who would make the dilution properly with an-hydrous peanut oil, we began to get uniform results.
Goodwin Breinin3 has demonstrated in the laboratory how the drug acts—it produces a facilitation of accommodation rather than an actual peripheral stimulation, as was originally thought. This confirmed what we had suspected clinically and explained why it has been rare for the drug to cause blurring of distant vision in low hyperopia or in
WHEELER MC. Isoflurophate (DFP) in the Handling of Esotropia. Arch Ophthalmol. 1964;71(3):298-302. doi:10.1001/archopht.1964.00970010314003