Amounts of prednisolone in breastmilk are very low. No adverse effect have been reported in breastfed infants with maternal use of any corticosteroid during breastfeeding. With high maternal doses, avoiding breastfeeding for 4 hours after a dose should markedly decrease the dose received by the infant. However, this maneuver is not necessary with short-term use. High doses might occasionally cause temporary loss of milk supply. Because absorption from the eye is limited, ophthalmic prednisolone would not be expected to cause any adverse effects in breastfed infants. To substantially diminish the amount of drug that reaches the breastmilk after using eye drops, place pressure over the tear duct by the corner of the eye for 1 minute or more, then remove the excess solution with an absorbent tissue.

A radioimmunoassay was developed for prednisolone using IgG purified from rabbit antiserum. The assay was employed to determine the pharmacokinetics of prednisolone following intravenous administration of 450 mg of prednisolone sodium succinate (Solu Delta Cortef) to five adult Thoroughbred horses. The RIA had a sensitivity of 2 ng/ml and was relatively specific. It had cross-reactivity with 21-deoxycortisol (83.3%) cortisol (27.8%), 11-beta-hydroxyprogesterone (39.2%) and 17-hydroxyprogesterone (50%). However, it did not cross-react with naturally occurring steroids (cholesterol, testosterone, estradiol or progesterone) or synthetic steroids (betamethasone, methylprednisolone, prednisone or triamcinolone). Radioimmunoassay of the horse serum samples detected the presence of prednisolone for 5 to 7 hours post administration. The pharmacokinetic parameters tested and their means were a half-life of 1.150 +/- 0.233 (+/- SEM) hours, an excretion constant of 0.686 +/- 0.018 Ke/hr, a volume of distribution of 607 +/- 109 ml/kg, and a clearance rate of 374 +/- 47 ml/hr/kg. RIA also detected the presence of prednisolone in the urine beginning one hour post administration. The prednisolone in the urine increased significantly at 2 hours and reached a peak at 4 hours post administration. The urinary levels decreased at 5, 6, and 7 hours and peaked again at 8 hours. The level then gradually decreased and reached the minimal detectable levels in 48 hours. These results showed that the RIA was sensitive and relatively specific for the determination of prednisolone.(ABSTRACT TRUNCATED AT 250 WORDS)

Prednisone and prednisolone are drugs with the potential for therapeutic inequivalence due to bioavailability problems. The objective of our study was to compare the systemic bioavailability of prednisolone from oral prednisone and prednisolone. Nine kidney transplant patients receiving prednisone (12.5 to 22.5 mg per day) were administered, in a randomized fashion, the same dose of oral prednisone (Deltasone), oral prednisolone (Delta-cortef) and intravenous prednisolone (Hydeltrasol). Prednisolone and prednisone levels were measured using a specific high-pressure liquid chromatographic assay. Since prednisolone exhibits dose-dependent pharmacokinetics because of nonlinear plasma protein binding, bioavailability from oral prednisone and oral prednisolone, compared to the intravenous dose, was 84.5 +/- 17.8% and 95.5 +/- 17.6% using unbound drug concentrations. These differences were not statistically significant. Furthermore, no significant differences were observed between the two oral formulations in peak prednisolone levels, time of peak levels or half-life using either total or unbound drug concentrations. The results from our study indicate that both of the oral preparations tested provide similar bioavailability of active prednisolone and the conversion of prednisone to prednisolone occurs rapidly.