a substance (Criteria A and B). Although recent  dose reduction or termination usually is
clear in the history, other diagnostic procedur es are very challenging if the drug is un-
known. Criterion B requires development of a “substance-specific syndrome” (i.e., the in-
dividual’s signs and sympto ms must correspond with th e known withdrawal syndrome
for the recently stopped drug)—a requirement that rarely can be met with an unknown
substance. Consequently, clinical judgment must guide such decisions when information
is this limited. Criterion D requ ires ruling out other medical conditions, mental disorders,
or withdrawals from familiar substances. When  the substance is known, it should be re-
flected in the name of the disorder upon coding (e.g., betel nut withdrawal).
Prevalence
The prevalence of other (or unknown) substance withdrawal is unknown.
Development and Course
Withdrawal signs commonly appe ar some hours after use of the substance is terminated,
but the onset and course vary greatly, depending on the dose typically used by the person
and the rate of elimination of the specific su bstance from the body. At peak severity, with-
drawal symptoms from some substances involve only mode rate levels of discomfort,
whereas withdrawal from other substances may be fatal. Withdrawal-associated dyspho-
ria often motivates relapse to substance us e. Withdrawal symptoms slowly abate over
days, weeks, or months, depending on the particular drug and dose s to which the indi-
vidual became tolerant.
Culture-Related Diagnostic Issues
Culture-related issues in diagnosis will vary with the particular substance.