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.
Illegal Drugs. Most street drugs, including heroin, cocaine and ecstasy can cause high blood pressure, stroke, heart failure and even death, in some cases from only one use. Cocaine, heroin and amphetamines also can cause kidney damage.