What is a potential effect of excessive CNS depression from xylazine?

Xylazine is a sedative commonly used in veterinary medicine, primarily for its calming effects on animals. One of the significant actions of xylazine is its ability to depress the central nervous system (CNS). When excessive CNS depression occurs due to high doses or sensitivity to the drug, a notable potential effect is respiratory depression. This occurs because the respiratory centers in the brain may become less responsive, leading to a decrease in the rate and depth of breathing.

Respiratory depression is a critical concern in cases of overdose, as it can lead to inadequate oxygenation and respiratory failure if not managed appropriately. Therefore, understanding this potential effect is crucial for veterinary professionals when administering xylazine or similar CNS-active drugs.

The other choices do not directly relate to the primary concerns surrounding excessive CNS depression from xylazine. Increased heart rate typically results from stimulation rather than depression, excessive urination is not a direct consequence of CNS effects, and visual impairment is not a typical or primary concern associated with xylazine-induced CNS depression.