The bloodshot appearance is due to the irritation and dilation of the surface blood vessel in the eye. Other symptoms can accompany the red appearance, like itching, soreness, discharge and even blurred vision. These symptoms could indicate a more serious problem.
The list of possible medications or substances mentioned in sources as possibe causes of Heart block includes: 1  Beta-adrenergic blockers. 2  Digitalis. 3  Flecainide. Flecatab. 4  Flumadine. Quinidine. 5  Rimantidine. Tambocor.
More common are drugs, referred to as alpha blockers, that relax the muscle in the prostate to reduce the tension on the urine tube. These include Hytrin, Cardura, Uroxatral, and Flomax. Side effects include light-headedness and weakness.