According to an online search, Morphine affects various body functions. Dogs and cats may vomit after administration. Dogs usually defecate immediately following injection. Panting may also occur. If necessary, the effects of the drug can be reversed with administration of naloxone.
Adverse effects associated with morphine include nausea, vomiting, slowed intestinal movement, constipation, restlessness, low blood pressure, slowed heart rate, slowed breathing, behavior changes and seizures.
The most profound adverse effects associated with morphine are suppression of breathing and sedation.
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