AMPHETAMINE
60% excreted unchanged within 48 hours in normal urine acidity.  Not 
readily detectable after 24 hours following a single dose.

BARBITURATES
Excreted slowly in general.  Approximately 8% is excreted in the first 
12 hours; 20% in 24 hours; 35-65% in 48 hours.  The long-acting 
barbiturates (e.g. phenobarbital) may be detected in urine in excess 
of four weeks after a single dose.

COCAINE
A single dose is excreted within 8 hours, depending on level of dosage 
and purity (Approximately 25-100 mg of pure cocaine is necessary for 
euphoric effect).

CODEINE
Excreted as free and conjugated codeine, and in part demethylated to 
morphine.  63-90% is excreted within 24 hours.

DILAUDID
90% is excreted within 24 hours, although traces amy be found for up 
to 48 hours.

MARIJUANA (THC)
Detectable from 3-10 days; 50% excreted within 3 days, and 50% 
excreted within 10 days following a single dose.  Detectable 25 days 
or more in chronic heavy users.

ALCOHOL
Decreases by .01 to .02 mg per deciliter per hour (Some have suggested 
noticable acceleration in alcoholism).

METHADONE
Les than 10% is excreted unchanged.  The remained is metabolized by 
N-demethylation.  Excretion is relatively rapid with the majority of a 
single dose excreted within 48 hours.

MORPHINE
Small amounts of free, and larger amounts of conjugated morphine is 
90% excreted within 24 hours.  Traces may be found up to 48 hours.

P.C.P.
Excreted generally unmetabolized within 24 hours following a single 
dose, but urine tests are often positive 7 days following ingestion.

METHAQUALONE
99% of a single dose is absorbed within 2 hours.  With an over all 
half-life of 18-42 hours, its ability of great protein binding makes 
its half-life biphasic; free drug serum measurements make it appear 
the drug is half gone after 2-3 hours. Not readily detectable after
24 hours following a single dose.

TALWIN (PENTAZOCINE)
Excreted within 24 hours following a single dose.

VALIUM (DIAZEPAM)
Serum half-life of 20-50 hours.  Some diazepam metabolites may be 
detected from 5-7 days following the initail dose.