Betagan (Levobunolol 0.25%, 0.5%)

Systemic absorption: Topical dosing can produce the same reactions as systemic beta-blockade, including death from bronchospasm in patients with asthma and, rarely, death associated with cardiac failure; ophthalmic beta-blockers may also impair compensatory tachycardia and increase risk of hypotension.

Cardiac failure: Beta-blockade may precipitate more severe failure where sympathetic support of the circulation is needed, and continued myocardial depression can lead to failure even in patients with no prior history; discontinue at the first sign or symptom.

Obstructive pulmonary disease: Patients with mild or moderate COPD or nonasthmatic bronchospastic disease should in general not receive a beta-blocker; if used, it may block bronchodilation from endogenous and exogenous beta-2 stimulation.

Vascular insufficiency: May potentiate syndromes associated with vascular insufficiency such as Raynaud's phenomenon.

Cerebrovascular insufficiency: Consider alternative therapy if signs of reduced cerebral blood flow appear.

Major surgery: Beta-blockade impairs reflex cardiac response; protracted severe hypotension and difficulty restarting the heartbeat have been reported under general anesthesia, so gradual withdrawal before elective surgery may be appropriate.

Diabetes mellitus: Masks the signs and symptoms of acute hypoglycemia; caution in labile diabetes and in patients on insulin or oral hypoglycemics.

Thyrotoxicosis: Masks tachycardia and other signs of hyperthyroidism; abrupt withdrawal may precipitate thyroid storm.

Muscle weakness: Beta-blockade may potentiate myasthenic symptoms including diplopia, ptosis, and generalized weakness.

Increased allergen reactivity: Patients with a history of severe anaphylaxis may be more reactive on repeat challenge and unresponsive to usual epinephrine doses.