Prescribing patterns of optometrists newly licensed in therapeutic drug use in New York State.

PURPOSE: As part of the New York State law authorizing optometrists to use Therapeutic Pharmaceutical Agents (TPAs), the New York State Education Department commissioned a study to monitor and assess the prescribing patterns and competence of optometrists newly licensed to use TPAs. This report summarizes the findings of that study. METHODS: The database was obtained from more than 11,000 Patient Data Reporting Forms (PDRFs) returned by 535 optometrists, listing diagnosis, type(s) of medication(s) prescribed, treatment outcome, and possible adverse effects. RESULTS: Of the more than 11,000 forms returned by 535 optometrists, 8,936 were first visits, with 5,828 follow-up visits scheduled. For all reported initial visits, only 89 patients required ophthalmological referral for secondary or tertiary care. No adverse drug reactions requiring intervention were reported. The most-frequent diagnoses treated by optometrists were related to allergies, superficial trauma, conjunctivitis (unspecified), and then blepharitis. The most commonly prescribed ophthalmic preparations as actually reported on the PDRFs were Polytrim (trimethoprim/ polymixin B), tobramycin (brand name and generic), TobraDex (tobramycin/dexamethasone), and Livostin (levocabastine). CONCLUSIONS: When analyzed according to diagnosis, the data indicate that the prescribing patterns of the prescribing optometrists adhered to currently accepted clinical guidelines. Based on the available data and the lack of observed side effects, the use of topical medications to treat anterior-segment disease by optometrists in New York State appears to be safe, and should be of benefit to patients who seek care from optometrists.

The clinical efficacy of paremyd with and without dapiprazole in subjects with light and dark brown irides.

BACKGROUND: Paremyd, a mydriatic formulation of 0.25% tropicamide and 1.0% hydroxyamphetamine hydrobromide provides adequate dilation for binocular indirect ophthalmoscopy in young Caucasians. We studied the clinical effectiveness of Paremyd in dilating heavily pigmented eyes by comparing its mydriatic efficacy in Blacks, Asians and Caucasians with light and dark brown irides. We also evaluated the efficacy of one drop of dapiprazole (Rev-Eyes) in reversing Paremyd-induced mydriasis in our subject sample. METHODS: In a masked, randomized, controlled experimental design, several visual functions which included pupillary dilation, near visual acuity, amplitude of accommodation, ocular hyperemia, and discomfort glare were measured at 30-min intervals, for a total of 300 min, in subjects dilated with a single drop of Paremyd in each eye. Ease of binocular indirect ophthalmoscopy was also assessed. A 3-way analysis of variance was used to assess changes in these measures as function of irides color/pigmentation (designated as light or dark brown iris color), presence or absence of dapiprazole, and test time interval. RESULTS: We found that subjects in our light brown irides group (mainly Caucasians) dilated faster than subjects in our dark brown irides group (mainly Blacks). Dapiprazole increased the speed of recovery from pupillary dilation for all subjects, but more so for those with light rather than dark brown irides. Similarly, subjects with light rather than dark brown irides recovered accommodative function more quickly. Although neither the use of dapiprazole nor the degree of iris color/pigmentation was significantly related to visual acuity or glare discomfort, there was a clear trend that these visual measures were affected to a greater degree in subjects with dark brown (primarily Blacks) rather than light brown irides. Overall, Paremyd provided adequate dilation for binocular indirect ophthalmoscopy in all subjects irrespective of iris color/pigmentation. CONCLUSIONS: Our data indicate that a single drop of Paremyd provides adequate mydriasis, without significant side effects, for routine fundus examination of all subjects, independent of iris color/pigmentation. Furthermore, a single drop of dapiprazole was effective in speeding the return of pupillary dilation in most subjects, but had no significant effect on accommodation, near visual acuity or glare discomfort. Side effects such as stinging upon instillation, conjunctival hyperemia, and a few instances of ptosis, with possible additional cost to patients, appear to lessen its overall clinical benefit.

Oral and topical antihistamines: pharmacologic properties and therapeutic potential in ocular allergic disease.

BACKGROUND: Allergic eye disease is a common clinical occurrence in individuals who experience local and systemic hypersensitivity reactions. The majority of ocular symptoms involve the conjunctiva and lids, which are exposed to the environment and thereby are sites of interaction between allergens and immunocompetent cells. Signs and symptoms of ocular involvement can manifest as itching, chemosis, tearing, swollen lids, and photophobia. METHODS: Histamine is a key preformed mediator released when allergen molecules crosslink to antigen-binding components of adjacent IgE molecules on mast cells or basophil surface. On its release, histamine acts on H1-receptors on a variety of tissues and cells, including blood vessels, smooth muscle, and sensory nerves. RESULTS: Drugs classified as H1-receptor antagonists, commonly referred to as the antihistamines, are among the most efficacious and frequently used medications for ocular and systemic allergy symptoms. CONCLUSION: This review focuses on the pharmacologic actions and side effects of oral first-generation sedating or classic H1-receptor antagonists; the second-generation, relatively nonsedating H1-receptor antagonists; and the topical ocular antihistamine/decongestants and single-entity antihistamine formulations.

Pupillary dilation and funduscopy with 1.0% hydroxyamphetamine plus 0.25% tropicamide (Paremyd) versus tropicamide (0.5 or 1.0%) as a function of iris and skin pigmentation, and age.

BACKGROUND: This study was designed to evaluate the effect of Paremyd, a combination of 1.0 percent hydroxyamphetamine hydrobromide and 0.25 percent tropicamide, on pupil size during binocular indirect ophthalmoscopy (BIO) upon 164 subjects of various skin pigmentation, iris color, and age. METHODS: Pupillary dilation and ease of performing BIO were measured after 30 minutes following instillation of a single drop of either Paremyd or tropicamide (1.0 or 0.5 percent) to an eye. Subjects were assigned to one of three groups; either Paremyd OU, or Paremyd OS and tropicamide (either 0.5 or 1.0 percent) OD, or Paremyd OD and tropicamide OS. Pupillary dilation was measured during BIO performed at a set illumination using a near point card. RESULTS: Results indicate that Paremyd is a significantly more effective dilator than either concentration of tropicamide alone. BIO was rated good to excellent for all dilating agents. As could be expected (based upon data from previous experiments), there was a small, but significant, negative correlation between dilation and age, skin pigmentation, and iris pigmentation. CONCLUSIONS: Paremyd, because of its superior effect upon dilation without side effects, can be the preferred agent used for routine single-drop dilation in all patients, independent of age, iris color, or skin color.

Drug therapy for ocular allergy.

Ocular allergy is a common problem for the primary care practitioner. A range of ocular decongestants, antihistamines, mast cell stabilizers, and corticosteroids are available for use, and practitioners must be familiar with the clinical effectiveness, treatment regimens, and side effects of these drugs. This paper reviews the drugs, both prescription and nonprescription, appropriate for management of ocular allergy and provides guidelines for their use.

Ocular side effects of selected systemic drugs.

Numerous systemic drugs produce adverse effects that involve the eye. Pigmentary inclusions of the lids or conjunctivae or both may be caused by a variety of drugs, including amiodarone, chlorpromazine, and gold salts, while conjunctivitis and blepharoconjunctivitis have been associated with isotretinoin, sulfonamides, salicylates, and antineoplastic agents. Dry eye complaints may be caused by antihistamines, beta-receptor blocking agents prescribed for cardiovascular problems, antianxiety agents, and tricyclic antidepressants. Several drugs have been well documented as causes of keratopathies and/or lenticular deposits, including chloroquine and hydroxychloroquine, chlorpromazine, gold salts, systemic corticosteroids, nonsteroidal antiinflammatory drugs, and the antiarrhythmic agent amiodarone. Visual acuity may be decreased by transient changes in refractive error caused by sulfonamides, the antifungal agent metronidazole, thiazide diuretics, and carbonic anhydrase inhibitors. Dilation of the pupil may be caused by anticholinergic drugs, antihistamines, antidepressant agents, and central nervous system stimulants such as cocaine, methylphenidate, and amphetamines. Nystagmus, diplopia, and extraocular muscle palsies have been associated with central nervous system depressants, antihistamines, barbiturates, and elevated blood ethanol concentrations. Intraocular pressure can be elevated in susceptible individuals by long-term use of topical or systemic corticosteroids. Numerous drugs have been associated with retinal toxicity, including chloroquine and hydroxychloroquine, thioridazine, tamoxifen, and talc, which may embolize to the retinal circulation when administered by long-term drug abusers. The antituberculosis agents ethambutol and isoniazid have been implicated as causes of reduced acuity, visual field defects, and disturbances of color vision. Optic neuritis and retrobulbar neuritis may result from the use of chloramphenicol. This paper describes these and other adverse ocular effects that may be encountered when examining patients who are taking systemic drugs.

Drug-related cataract.

Associations between drug therapy and development of lenticular changes have been documented in the literature. Drugs most frequently implicated include corticosteroids, phenothiazines, miotics, gold, amiodarone, and allopurinol. The reported clinical observations on these agents are described, and similarities and differences between these drugs in regard to location of opacities and possible pathogenesis are discussed.

Toxic effects of ophthalmic preservatives on cultured rabbit corneal epithelium.

We investigated the effects of the ophthalmic preservatives thimerosal and sorbic acid on the proliferation and survival of rabbit corneal epithelial cells in tissue culture. Normally, explants of corneal epithelium grow vigorously during the first 7 days in culture. With 0.004% thimerosal present in the culture medium, the normal proliferation of corneal cells is suppressed completely. When 0.1% sorbic acid is present, proliferation is delayed and the lifespan of the corneal cells is reduced. After a 1-h exposure to concentrations of thimerosal of 0.0005% or greater, virtually all corneal cells present in established cultures are killed. These results suggest that use of ophthalmic preparations containing these chemicals may affect the metabolic and proliferative capacity of the corneal epithelium adversely.

Use of diagnostic pharmaceutical agents and incidence of adverse effects.

A drug registry was established at Southern California College of Optometry (SCCO) to study use rates and incidence of adverse side effects of the nine pharmaceutical agents in the California optometry law. Data were gathered in clinics of SCCO for 6 months and offices of 20 private practitioners for 3 months. Data included drugs used, the strength and dosage, patient age, sex, and racial or ethnic origin. Adverse drug reactions were reported in detail, including objective and subjective findings, duration of the reaction, and case disposition. A total of 12,493 drug applications were reported. A low incidence of adverse reactions, eight cases (0.208%), which produced no permanent effects, is sound evidence regarding the risk/benefit ratio in support of the use of pharmaceutical agents by optometrists.

Effect of tropicamide on ocular blood flow in the rabbit.

Intracardiac injection of 15 microspheres labeled with 85Sr (strontium) and 141CE (cerium) were used to determine ocular blood flow in seven rabbits before and 25 min after bilateral application of tropicamide to the cornea. By using two different isotopes distinguishable under gammaspectrometry, each animal served as its own control. After administration of two drops of 1% tropicamide, no significant difference in blood flow between treated and untreated eyes was observed.

Analysis of the role of cyclic adenosine 3',5'-monophosphate in catecholamine release.

1. Cyclic adenosine 3',5'-monophosphate (cyclic AMP) levels and catecholamine release were measured in cat adrenal glands perfused in situ with Locke solution.2. Cyclic AMP was present in the medulla in an amount which represented approximately one fifth of that present in the cortex.3. Perfusion with acetylcholine (ACh) or nicotine increased cyclic AMP both in the intact adrenal and in the perfusate. The time course of the changes in tissue cyclic AMP during stimulation was out of phase with the time course of catecholamine release. Maximal increases in cyclic AMP were not manifest until after 8 min of exposure to the secretogogue, whereas maximal rates of secretion occurred during the first minute.4. Theophylline (0.5 mM) increased basal and stimulated adrenal cyclic AMP levels, but did not potentiate the secretory response to ACh or nicotine.5. Perfusion with cyclic AMP or its dibutyryl derivative (0.2-4 mM) failed to effect a consistent or significant increase in the rate of catecholamine release and was unable to potentiate the secretory response to a submaximal concentration of ACh or calcium.6. The results suggest that, unlike calcium, cyclic AMP is not a direct mediator of medullary secretion.

The effect of ACTH on calcium distribution in the perfused cat adrenal gland.

1. Experiments were carried out to study the effects of adrenocorticotrophin (ACTH) on calcium distribution in the isolated cat adrenal gland perfused with Locke solution.2. The addition of ACTH to Locke solution caused a small, but significant, increase in the radiocalcium ((45)Ca) space and content of the adrenal cortex.3. The average (45)Ca washout curve obtained after exposure to ACTH was significantly displaced above the average washout curve for the control glands during the first 20 min of washout. During the time that the two curves were significantly different, maximum corticosteroid secretion was attained.4. The rate of (45)Ca efflux was slowed after ACTH was added to the perfusion medium.5. The total calcium content of the cortex was not altered by ACTH.6. Perfusion with calcium-free Locke caused a rapid decrease in the calcium content of the cortex to about 20% of the control value. Dinitrophenol was required to deplete completely the cortical calcium content during perfusion with the calcium-deprived medium.7. The results are consistent with the suggestion that a translocation of calcium occurs during stimulation of the cortex by ACTH. The source of the calcium ions needed to support the secretory response to ACTH is probably not the extracellular fluid; but ACTH may shift calcium from a rapidly exchanging to a more slowly exchanging cellular pool.