Drug rehabilitation is a painful thing, but in order to return to normal life, many determined drug addicts still use this means. In order to help them quit drugs better, medical experts have specially developed some anti-addiction drugs for their use. The most common and popular methods nowadays are the three drug rehabilitation decrement methods listed below: Methadone replacement decrement method. Methadone is a synthetic anesthetic with pharmacological effects similar to morphine. It has a long duration of action and good oral effect. These two characteristics make it the main drug for substitution decrement method. Since it does not produce toxic effects on human thinking and behavior, it is also used as methadone maintenance therapy. The side effects of methadone are similar to those of morphine. The common ones are constipation, sweating, sedation, sexual desire inhibition, and sometimes edema in the lower limbs in women. Except for the persistent constipation, other side effects can gradually adapt and become mild. Opiate decrement method. The opiate decrement method has been used for the longest time in our country. It is obviously effective for detoxification of opiate dependence. It is clinically safe to use, with few side effects, and is suitable for opium or milder heroin addiction. The dosage of the opiate decrement method should be appropriate. A larger dose makes it difficult to reduce and withdraw from the drug, while a smaller dose fails to achieve the purpose of alleviating withdrawal symptoms. The principle of individual differences and individualized dosage should be followed, taking into account the years of drug abuse, daily drug abuse, the severity of withdrawal symptoms, and the amount of drug abuse in the past two weeks to determine the initial dosage, and then adjust according to the situation of controlling withdrawal symptoms. The opiate decrement method can usually be completed within 10 days, and in individual cases, it may take more than two weeks. Buprenorphine decrement method. Buprenorphine is a semi-synthetic derivative of thebaine. It is both an opiate agonist and an antagonist, with strong analgesic effects and long-lasting action. Its analgesic intensity is about 100 times that of morphine. The analgesic activity is 25 times that of morphine, that is, 0.4 mg of buprenorphine is equivalent to the analgesic intensity of 50 mg of morphine. The analgesic effect of buprenorphine lasts longer, injections can last 6-8 hours, sublingual tablets can last 8-12 hours, which is about 1.5-3 times the duration of morphine's analgesic effect. Buprenorphine is quickly absorbed, reaching peak blood concentration within minutes. It is mainly metabolized in the liver, excreted through bile, and excreted through feces. It can penetrate the blood-brain and placental barriers.