Ocular tissue absorption of minocycline in the rabbit.

After intramuscular (IM) administration of minocycline hydrochloride, concentrations of the drug that would be adequate for the control of sensitive organisms (greater than 0.5 micrograms/g of tissue) were detectable in the cornea, iris, and retinochoroid 3, 6, and 12 hours after a single injection. The concentration of the drug in the aqueous humor was greater than in the vitreous humor. Following a single IM injection of 40 mg/kg, the drug level was found to be significantly higher in the iris and aqueous humor of pigmented rabbits than in the corresponding tissues of albino rabbits. The drug seems to concentrate in the pigmented layers of the ocular tissue.