Drug action in general depends on the dosage, potency, drug interactions, metabolism and changes in the brain chemistry. [University of Waterloo] Drugs interfere with the homeostasis of the body and prolonged use creates long-term changes in the brain. Thus withdrawal symptoms manifest upon stoppage of drug use. The body tends to be accustomed to the presence of the drug and hence withdrawal as such leads to unmanageability of bodily functions, at least temporarily. (Withdrawal period). The levels of naturally occurring brain chemicals are modulated by drug usage, resulting in a situation where the brain is not able to respond normally upon withdrawal, as it is conditioned to the presence of the drug in the body. For example, patients under long-term use of anti depressants have unusually increased levels of mono amine neurotransmitters. These changes in the brain an

Some common words found in the essay are:
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Approximate Word count = 587
Approximate Pages = 2 (250 words per page double spaced)