Study on the effect of the combination of propranolol hydrochloride and pilocarpine hydrochloride on intraocular pressure of rabbit's eye

ABSTRACT

Pilocarpine hydrochloride and /or propranolol hydrochloride were formulated in aqueous solutions and gel form using methyl cellulose and sodium carboxymethylcellulose as thickening and gelling agents, respectively. Both formulations were instilled into normal rabbit's eyes and the changes in the intraocular pressure [IOP] were determined. It was found that the action of both drugs on the intraocular pressure was significantly increased in the presence of the added polymers. Moreover, the optimum decrease in IOP was reached in a shorter time with aqueous solution [2 h] and gel form [3 h] than with control drugs without polymer [4 h]. The peak heights of such decrease were in percentage for pilocarpine hydrochloride 7.2, 27.5 and 17.9, for propranolol hydrochloride 12.5, 18.4 and 17.3 and for their mixture 15.4, 15.4, 15.4 and 16 as aqueous solution, aqueous solution with methylcellulose and gel form, respectively. The study showed that the use of propranolol hydrochloride with pilocarpine hydrochloride with pilocarpine hydrochloride in a concentration of 1% each causes a maximal decrease in IOP in presence of methylcellulose as a thickening agent