Intraocular pressure, in glaucoma

Blockers can reduce intraocular pressure in glaucoma and ocular hypertension. The mechanism is believed to be related to a decreased production of aqueous humor. 

Glaucoma Timolol and other ocular P-blockers are used to treat glaucoma. Propranolol is effective in diminishing intraocular pressure in glaucoma. This occurs by decreasing the secretion of aqueous humor by ciliary epithelium. It neither affects the ability of eye to focus for near vision, nor changes pupil size. Used in chronic cases only. 

Therapeutic THC is called dronabinol (Marinol) and has been marketed with approval by the Food and Drug Administration to reduce nausea and vomiting in patients undergoing cancer chemotherapy and to stimulate appetite in AIDS patients. It has also been shown to reduce intraocular pressure in glaucoma. Levonantradol, an analog, may be useful as an analgesic. 

Dorzolamide can be applied topically to the eye to lower intraocular pressure in glaucoma (p.346). 

Hughes E, Spry P, Diamond J. 24-Hour monitoring of intraocular pressure in glaucoma management a retrospective review. J Glaucoma 2003 12 232-236. 

Figure 28-28 Dorzolamide (Trusopt), 1. also a constituent of Cosopt, was the first drug designed with structure-based CAOO methods to become commercially available. MK-927. 21, IS a close structural analogue and was the first carbonic anhydrase inhibitor to lower intraocular pressure In glaucoma patients...

Aceclidine is mostly used in ophthalmology for constriction of the pupil and reduction of intraocular pressure in glaucoma. Oxylidine is being used as a tranquilliser in patients with neurotic states and early states of hypertension. It is also recommended for the treatment of cerebral atherosclerosis. Its oral dose is 0.02—0.5 g. Qualidile is a curare-like drug used in general anaesthesia. The preparation is injected intravenously at a dose of 1 mg kg S muscle relaxation lasts for 10 minutes, slight inhibition of respiration being observed. A dose of 2 mg kg produces complete relaxation of the skeletal muscles, accompanied by apnoea. In spite of the fact that the review is well documented, it is difficult to form an idea about the clinical merits of these compounds. Some clinical information has been published recently a comparison of Qualidile with NiV -diallyl-bisnortoxiferine or tubocurarine chlorides loc. cit.) would be of special interest. 

Leopold, I. H. (1984), The use and side effects of cholinergic agents in the management of intraocular pressure. In Glaucoma Applied Pharmacology in Medical Treatment (S. M. Drance and A, H. Neufeld, Eds.), pp. 357-393. Grune Stratton, Orlando, FL. 

Isosorbide is basically a bicyclic form of sorbitol that is used orally to cause a reduction in intraocular pressure in glaucoma cases. Although a diuretic effect is noted, its ophthalmologic properties are its primary value. 

Pilocarpine an imidazole alkaloid, and the chief alkaloid from the leaves of Brazilian Pilocarpus species. M, 208.26, m.p. 34 °C, b.p.j 260 C, [a]g -100.5° (CHCI3). P. is used therapeutically as a diaphoretic, i.e. to induce sweating, and especially in nephritis to relieve the kidneys and remove toxic metabolites. It is also used in opthalmology as an antagonist of atropine, and for regulating the intraocular pressure in glaucoma. 

THC is a lipophilic compound—quickly absorbed but slowly excreted—and responsible for most of the pharmacologic actions of cannabis. Therapeutically it is euphoric, sedative, anti-nauseant, appetite stimulant, bronchodilator and reduces intraocular pressure in glaucoma. However, legal restrictions mean that most use of the herb is illicit. The euphoric effects of the herb are well documented, as are the psychological dependence and disruptive effects on memory and cognitive processes. Its use has also been linked to infertility (Sethi et al. 1991). However, acute toxicity is very low and there are few if any documented cases of fatalities from cannabis use (Bruneton 1995). 

Improvement of ocular absorption of polar drags can be achieved by the prodrag approach, the major problem being the attainment of an optimal drag concentration at the site of action within the eye due to poor absorption through the cornea. Adrenaline lowers intraocular pressure in glaucoma cases, but is poorly absorbed because it is highly polar. It also has a short duration of action... 

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