Morphine effects on the central nervous system, the gastrointestinal system, and the cardiovascular system vary in importance and degree.
Generally speaking, since morphine is an opiate and analgesic, it relieves pain, causes euphoria, inhibits hunger, relieves fear and anxiety, impairs physical and mental performance, and has other opiate associated effects. Named after the Greek god of Dreams, Morpheus, it has also been known to induce hallucinations.
Although morphine was first isolated in 1804, it was not until 1853 (with the invention of the hypodermic needle) that morphine began to be widely used. Since then morphine effects on the body have been recognized as being both beneficial (for pain relief) and malign (when addiction ensues).
Morphine effects are produced in the central nervous system by directly influencing the cerebral opioid receptor system in the brain. Because of this, morphine effects are stronger than any other narcotic analgesic. Of all bodily systems, morphine effects are most significantly induced by morphine’s affect on the central nervous system.
Morphine effects are also seen in many patients and users in the form of constipation. Morphine effects like this in the gastrointestinal system are a result of how morphine interacts with certain opioid receptors in the bowel: it inhibits gastric emptying and slow down intestinal transit.
Lastly, opinions on morphine effects on the cardiovascular system differ. While some studies, such as one conducted by the International Anesthesia Research Society, indicate that morphine can initially stimulate hemodynamics and increasing oxygen intake, other experts maintain that morphine slows the heart rate, reduces blood pressure, and decreases respiration.