Mainly in medicine, opiates are used because of their analgesic effect. As noted above, opiates have been used for this purpose for centuries, and to this day they remain the most powerful and selectively effective anesthetics known to medicine. Unlike anesthetic drugs such as depressants, analgesics-opiates anesthetize without impairment of consciousness. After taking a moderate dose of opiates, patients remain conscious and are still able to talk about pain, but no longer suffer from pain.

Another class of substances that has a similar analgesic effect are such common painkillers: aspirin, acetaminophen and ibuprofen. Table 9-1 shows the main opiates used as painkillers along with their effectiveness and duration of activity. As noted, the effectiveness of the drug is the dose required for the desired effect. In Table 9-1, the strength of a drug is expressed in terms of the amount of effective doses of morphine. For example, the effectiveness of heroin is indicated by the number 4. This means that if 8 mg of morphine is required for pain relief, then heroin will need only 2 mg. In other words, heroin is 4 times stronger than morphine. Morphine is a prototype of opiate analgesics and is used as a unit for measuring the effectiveness of other drugs. It is used mainly for very severe pain. Although heroin is much stronger than morphine, it is not used for medical purposes in the United States, because is included in the N1 Drug Group (see Appendix N1) Table 9-1 Characteristics of the main opiates Common name Trademark Effectiveness Duration (in hours) Morphine 1 4-5 Heroin 4 3-4 Hydromorphone Dilaudid 5 4-5 Codeine 0.1 4-6 Oxycodone Percodan 0-75 4-5 Methadone Dolophine 1 24-48 Mepredin Demerol 0-1 2-4 Propoxyphene Darvon 0-5 6 Fentanyl Sublimaze 80 1-3 Pentazocin Talwin 0-2 2-3

When the pain is not so strong, you can use drugs that are less effective than morphine. These are codeine, propoxifen (Darvon), oxycadone (Percodan) and pentazocine (Talwin), which are often prescribed for pain relief. In conclusion, we note that there are opiates that are more effective than heroin: for example, fentanyl, which is more effective than morphine 80 times. Fentanyl is mainly used for anesthesia. In general, opiates are the most powerful and effective pain medication known to medicine. Restrictions in their use as analgesics, occurs mainly due to their ability to induce tolerance and dependence. Tolerance and dependence are caused by the use of all these drugs, although it seems that some, for example, pentazocine (Talwin) cause these effects to a lesser extent. It is hoped that safer analgesics will be invented after endorphins have been better studied and their ability to cause natural pain relief.

Opioids are used in medicine and for other purposes. For example, opiates cause constipation, which can be a problem for drug addicts. Therefore, it is advisable to use them in the treatment of diarrhea. Opioids are still used to treat cough. Basically, dextromethorphan is used for this purpose, which is a synthetic opiate that does not have an analgesic effect and does not cause dependence, but is very effective in suppressing cough. The last medical use of opiates, such as methadone, is to use them to treat heroin addiction.