Thanks again everyone.

Carol, I have had the same issue Laurel mentioned - the black stopper gets too "sticky" and won’t slide in and out anymore. I bet you are right that the ones specifically made for oral meds last longer. I am going to try the $2.69 OTC Walgreens one. The little 3ml I have been using was a leftover from the liquid Cortef days many years ago and I think it has just reached the end of its life expectancy.