A nurse is providing teaching to a client who has a new prescription for timolol to treat open-angle glaucoma. Which of the following adverse effects should the nurse include in the teaching?

Rationale: A. Strabismus: Strabismus, or misalignment of the eyes, is not a known adverse effect of timolol. Timolol primarily affects intraocular pressure and systemic cardiovascular parameters rather than eye muscle alignment. B. Bradycardia: Timolol is a nonselective beta-adrenergic blocker that can be absorbed systemically even when administered as eye drops. One potential systemic adverse effect is bradycardia, as the medication can reduce heart rate and cardiac output, particularly in clients with preexisting heart conditions. C. Conjunctivitis: While eye irritation or mild stinging can occur with timolol, conjunctivitis is not a typical adverse effect. Instructing clients to monitor for more common ocular side effects, such as burning or discomfort, is appropriate. D. Hyperglycemia: Timolol does not typically cause hyperglycemia. Beta-blockers can sometimes mask hypoglycemia symptoms in diabetic clients but are not associated with raising blood glucose levels directly.