1. Constipation: Similar to opioids, morphine reduces gut motility by acting on the myenteric plexus in the intestinal tract, resulting in constipation.
  2. Addiction: As with all other opioids, morphine is highly addictive as mentioned in the American Civil War and the Great War of 1914-18.  In certain studies under controlled environment, which compared the physiological and subjective effects of injected heroin and morphine in addicts formerly users of opiates, they exhibited no preference for one drug over the other with both being equally effective, with no difference in feelings of euphoria, ambition, nervousness, relaxation, drowsiness, or sleepiness, when they rated themselves.
  3. Withdrawal: Ceasing use of morphine creates a typical withdrawal syndrome akin to all opioids, which is not fatal by itself in healthy patients like the withdrawal symptoms of barbiturates and benzodiazepines.

Overdose: A large overdose can result in asphyxia and death by respiratory depression if there is no timely medical intervention. Naloxone helps in stabilizing cases of morphine overdose as it reverses morphine’s effects but it may require multiple doses.

Contraindications: The following conditions are relative contraindications for morphine:

  1. Acute respiratory depression
  2. Renal failure
  3. Chemical toxicity (potentially lethal in low-tolerance patients)
  4. Raised intracranial pressure which may induce head trauma (risk of worsening respiratory depression).
  5. Biliary colic.

WARNINGS: Morphine is a very beneficial medicinal agent with great utility purposes but has considerable potential for harmful effects, which includes psychological and physical tolerance and dependence. Withdrawal symptoms are most likely to occur on its abrupt discontinuation or administration. It, like other opiates, produces relaxation, indifference to pain and stress, lethargy, and euphoria. Subjects who receive narcotics on a regular basis for prolonged periods of time will have a tendency to exhibit mild symptoms upon discontinuation and may not be recognizable as withdrawal symptoms. However, the majority of opiate-dependent patients who receive them for medical reasons do not develop drug-seeking behavior or compulsive drug use. Personality traits play a major role in determining who are likely to become abusers. Morphine and other opiates should be used only if other medicines less hazardous are ineffective, and acknowledging the possibility of its masking significant manifestations of disease which should be identified for proper diagnosis and treatment.