Physical Dependence Open Access Articles

 The effects of big doses of morphine in intolerant and tolerant rats also because the importance of suddenly withdrawing morphine in rats experimentally enthusiastic to large doses of morphine are studied on weight , temperature, rate , rate of respiration , water consumption and various kinds of motor activity and behavior. In confirmation of the various early reports, tolerance develops to certain depressant actions of giant doses of morphine and thus the consequences of morphine within the tolerant rat are primarily excitation, consisting of a rise in blood heat , rate and motor activity. The fasting syndrome of rats eager to large doses of drug seems to carry two phases:  An early phase, which has been called “primary abstinence” consists of weight loss, an increased number of “wet dog” shakes, increased activity, and a fall in body temperature and rate .the first abstinence disorder becomes clearly glaring within 8 to 16 hours following the last dose of morphine and persists for about 72 hours.  The secondary abstinence problem emerges thereafter and consists of a rapid gain in weight , elevated body temperature and rate and an increase in water consumption. The secondary abstinence syndrome is protracted and tiny differences are seen between addicted and control animals as long as four to six months after withdrawal of morphine.