1. USE OF LOCAL ANESTHETICS
Unsupervised self-administration of local anesthetics is dangerous because they are toxic to the corneal epithelium, delay healing, and the patient may further injure an anesthetized eye without knowing it.
et al. Toxic keratopathy associated with abuse of topical anesthetics and amniotic membrane transplantation for treatment. Int J Ophthalmol. 2015 Oct 18;8(5):938–44.
Dilating the pupil can very occasionally precipitate acute glaucoma if the patient has a narrow anterior chamber angle and should be undertaken with caution if the anterior chamber is obviously shallow (readily determined by oblique illumination of the anterior segment of the eye). A short-acting mydriatic, such as tropicamide, should be used and the patient warned to report immediately if ocular discomfort or redness develops. Angle closure is more likely to occur if pilocarpine is used to overcome pupillary dilation than if the pupil is allowed to constrict naturally.
et al. A review of drug-induced acute angle closure glaucoma for non-ophthalmologists. Qatar Med J. 2015 May 10;2015(1):6.
et al. Ability of non-ophthalmologist doctors to detect eyes with occludable angles using the flashlight test. Int Ophthalmol. 2014 Jun;34(3):557–61.
3. CORTICOSTEROID THERAPY
Comanagement with eye specialists is strongly recommended to monitor for ocular complications of corticosteroid therapy. Long-term use of local corticosteroids presents several hazards: ocular hypertension leading to open-angle glaucoma; cataract formation; and exacerbation of ocular infections, such as herpes simplex (dendritic) and fungal keratitis. Furthermore, perforation of the cornea may occur when corticosteroids are used indiscriminately for infectious keratitis. The potential for causing or exacerbating systemic hypertension, diabetes mellitus, gastritis, osteoporosis, or glaucoma must always be borne in mind when systemic corticosteroids are prescribed for such conditions as uveitis or giant cell arteritis.
4. CONTAMINATED EYE MEDICATIONS
Ophthalmic solutions are prepared with the same degree of care as fluids intended for intravenous administration, but once bottles are opened there is always a risk of contamination, particularly with solutions of tetracaine, proparacaine, fluorescein, and any preservative-free preparations. Single-use fluorescein eye drops or sterile fluorescein filter paper strips are recommended for use in place of multiple-use fluorescein solutions.
Whether in plastic or glass containers, eye solutions should not remain in use for long periods after the bottle is opened. Four weeks after opening is the usual maximum time for use of a solution containing preservatives before discarding. Preservative-free preparations should be kept refrigerated and usually discarded within 1 week after opening. Single-use products should not be reused.
If the eye has been injured by accident or by surgical trauma, it is of the greatest importance to use freshly opened bottles of sterile medications or single-use products.