The influence of dexamethasone 0.1% eye drops on plasma cortisol and ACTH concentrations after cataract surgery

The present study evaluates the systemic absorption after the application of dexamethasone 0.1% eye drops every hour in patients following cataract surgery. The changes of the plasma cortisol concentrations, ACTH concentrations, saliva and urine cortisol concentrations were examined before and after cataract surgery. The above-mentioned parameters were analyzed in 13 patients following phacoemulsification and IOL implantation. The data were determined before and on the third postoperative day. Dexamethasone 0.1% eye drops were applied after surgery to the operated eye every hour for 3 days. All cortisol levels decreased on average. On the third postoperative day, saliva cortisol (measured hourly from 8 a.m. to 10 p.m.), urine cortisol (24 h) and plasma cortisol were lowered compared to the first preoperative examination. In contrast, the ACTH concentrations increased on average. The decrease in plasma cortisol from 12.3 +/- 7.1 to 8.05 +/- 3.7 micrograms/dl was statistically significant (p < 0.05) as well as the flattening of the sputum cortisol concentrations on the third postoperative day. All data were within the physiological range. The present study demonstrates considerable systemic absorption of ophthalmic dexamethasone 0.1% eye drops which results in decreased plasma cortisol concentrations and lowering of the saliva cortisol concentration at certain hours of the day with no change of the circadian rhythm.