The usage of opium in Medical 鸦片在医学上的运用

》 Analgesic effect
Significant analgesic effect of morphine and highly selective analgesic, not only the patient's consciousness is unaffected, there is also the other senses. The effectiveness of the persistent pain (chronic pain) than its intermittent sharp pain. Such as increasing the dose of sharp pain. Analgesic principles in addition to increasing the pain threshold, pain response to change is also an important factor. With morphine, the pain stimulus usual feel like tension, fear, and retreat the ordinary proper response already disappeared, the patients' pain, but not bitter. Unpleasant mood often accompanied by pain if they are canceled, the pain will be easier to tolerate. Analgesic effect of codeine is about 1/4 of morphine.

》Hypnotic effects
Hypnotic effects of morphine, but the sleep light and easy to wake up, can not be regarded as a true hypnotics. Codeine does not lead to sleep.

》 Respiratory depression antitussive effect
Highly selective inhibition of morphine on the respiratory center inhibition of breathing has been lower than the analgesic dose. At this time, the respiratory center to reduce the sensitivity of CO2 that can be used to treat breathing difficulties (cardiac asthma). The first performance of respiratory depression frequency reduction at this time due to the depth of greater compensatory role, no amount of ventilation influence. Poisoning due to inhibition of the deepening, the frequency is reduced too much, to increase the depth of breathing also can not be compensated, and severe hypoxia. The paralysis of the respiratory center to the morphine poisoning direct cause of death. Codeine, morphine respiratory depression far lighter.

Role of morphine, the carotid body chemoreceptors reactive improve, which is the result of respiratory depression caused by hypoxia. The morphine poisoning breathing maintaining depends on hypoxic chemoreceptor stimulation. At this point, if inhaled pure oxygen or high concentrations of oxygen, can automatically breathing stopped immediately, and therefore oxygen should provide artificial respiration. Papaverine can function in the carotid sinus and aortic body chemoreceptors the mild excitement breathe, but no great significance in the treatment of

Cough effect of morphine is also very strong, mainly due to the suppression of the cough center. Cough desired dose smaller than the analgesic, e.g. 2 to 4 mg of morphine can produce significant cough effect, while the analgesic need of 5 to 15 mg. Codeine less antitussive role than morphine, but has enough satisfaction, but many shortcomings (no morphine addictive, prone to cause constipation, inhibition of respiration, etc.), so for the most commonly used antitussive. Noscapine has antitussive effect of codeine equal, but no other central inhibition does not produce mental or physical dependence, nor inhibit breathing animals, a large number of anti-excited breathing.

》 Role on the cardiovascular system
Therapeutic doses little role in the supine patient's blood pressure, heart rate and rhythm, no significant effect on the vasomotor center. However, orthostatic hypotension may occur. Morphine diastolic small peripheral blood vessels and the release of histamine. Patient morphine hypovolemia cause hypotension, morphine and phenothiazine drugs synergy of respiratory depression and hypotension caused dangerous. Pulmonary heart patients morphine had caused the death of the report, must be noted.

Papaverine to relax various smooth muscles, particularly in the aortic smooth muscle (including coronary artery, cerebral artery, peripheral artery and the pulmonary artery), the presence of spasm, relaxation effect is more significant. Can be used for peripheral artery or pulmonary embolism. The dog long Shuzhang Guan-like blood vessels and increase the role of the coronary blood flow, but its performance positive inotropic and systolic blood pressure decreased role, it is not sufficient to prevent angina. Large doses depress myocardial conduction and prolong the refractory period, the amount of treatment had no significant effect on the electrocardiogram, high-dose prevents chloroform - adrenaline-induced cardiac fibrillation.

Noscapine also can inhibit smooth muscle and cardiac, but in the antitussive doses, these effects do not appear.

》 Gastrointestinal and other smooth muscle organs
Morphine can cause constipation, mainly due to the gastrointestinal tract and its sphincter to improve the secretion of digestive juice reduced and they intended to slow, making the contents of the gastrointestinal tract forward movement greatly delay. Therapeutic doses of morphine so that biliary pressure increased significantly, and the patient felt abdominal discomfort, and even the occurrence of biliary colic. Biliary spasm, should not be used (or with the use of antispasmodic drugs), morphine make Oddi's sphincter contraction, prevent emptying, thus increasing the tube pressure. The role is far weaker than morphine, codeine inhibit peristalsis are unlikely to cause constipation.
While a large number of morphine can bronchoconstriction, but it is a rare occurrence in the amount of treatment, reports of death of morphine during the occurrence of bronchial asthma, it is disabled morphine.
Papaverine can inhibit intestinal smooth muscle but is very weak, it can not eliminate the bile duct spasm caused by the morphine, methacholine-induced asthma (person) is also invalid.

Miotic effect of morphine, there are significant, as one of the bases of morphine poisoning diagnosis.

》 Other
After repeated morphine tolerance, but only the central inhibition tolerated, analgesic, hypnotic, inhibition of respiration, its excitatory effects and the role of the pupil, smooth muscle, no tolerated. Morphine addiction is often constipation, miosis. General tolerance for taking 2 to 3 weeks after. Tolerated after stopping in a few days to two weeks or less disappeared. As then 2nd tolerated generate faster. Addiction tolerated dose available to ordinary therapeutic dose of 20 to 200 times, and even a daily use 5 grams without poisoning. The tolerated generation was probably due to some nerve tissue reduced sensitivity to morphine.

Where for taking morphine for more than two weeks, the patients can into morphine, and sometimes even served a few days to addiction. After the addiction, the patients in each taking soon euphoria (euphoria of a mood changes in patients in a special "happy" state, carefree, mentally and physically on painful left unchecked, the indifference. Such a special "happy" status is an important reason to cause addiction. correct judgment and reasoning ability also exists in the euphoria of morphine, a critical attitude towards their individual moves and acts at the same time completely saved, kinesiology accessibility, its performance for hi lonely, indulge in fantasies). To not morphine, 5 to 8 hours after signs of serious withdrawal symptoms. Addicts is very sluggish, and the excited state, the extent of up to paroxysmal crying and yelling, constantly begging to be given morphine. Yawning and sneezing, tears exchanges, sweat dripping. Vomiting and diarrhea may also occur. Can not sleep. For 2 to 3 days, so most of the symptoms start to subside. Sometimes also circulatory collapse and loss of consciousness. Such as give sufficient quantity morphine, all withdrawal phenomena disappear immediately. Morphine addiction withdrawal treatment is more difficult, and easy to relapse.
Codeine "euphoric" disease and addiction are very low. Papaverine and noscapine not addictive.