Hello and thanks for the query
Pethidine has an analgesic potency approximately equal to one-fifth that of morphine. Pethidine binds to the opioid receptors in the central nervous system and exerts it’s main pharmacological action on the central nervous system.dependency can occur with it's use.
Pethidine must be regarded as drug of addiction.

Another opiate stronger than pethidine is morphine.
Morphine is a type of narcotic, opiate ingredient used in many different pain medications. Because it is classified as a controlled substance, there are special laws controlling its sale and use. The medication also has a significant potential for both psychological and physical dependence and abuse. 
In fact all the opiates should be used with caution and under strict observation and guidance of your treating doctor.
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