Page 438 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

Toxicity of Drugs of Abuse Chapter | 22 405

VetBooks.ir Nonhuman primates have increased heart and respiratory boiled into a soup for ingestion. Peyote grows in the
southwestern United States and Mexico and is used
rates, hypertension, and tonic-clonic seizures (Christie
legally by indigenous people. A tuberous root grows into
et al., 2013).
the ground and is capped by crowns or “buttons” which
Treatment are removed. The buttons may contain 1.5% mescaline on
a dry matter basis. Buttons can be eaten fresh but are
Prognosis for an animal overdosed with phencyclidine or
often dried. Dried buttons are chewed, powdered, recon-
ketamine is generally good with early intervention, but
stituted, or steeped into a tea. Pickled buttons have caused
self-induced trauma and rhabdomyolysis are possible
botulism (Halpern, 2004). Though traditional uses are per-
complications. Cats that have undergone ketamine anes-
mitted, mescaline is a Schedule I drug.
thesia usually recover rapidly and are able to sit up within
Mescaline is well absorbed by oral and parenteral
2h (Branson, 2001). Dogs injected with low doses of
routes in the dog, with maximum plasma concentrations
phencyclidine (1 mg/kg IM) recovered almost completely
detected within an hour of ingestion. Mescaline concen-
in a little over an hour, and at higher doses (5 mg/kg)
trations detected in the brain reflect blood concentrations.
were able to sit up within 2 h (Ortega, 1967).
Renal, hepatic, and splenic concentrations are three to six
Treatment of phencyclidine or ketamine overdose is
times blood concentrations. Mescaline can be detected in
generally symptomatic and supportive. Animals must be
the urine within 30 min of exposure and remains
kept in a dark, quiet room and restraint is to be avoided.
detectable for up to 24 h. Between 28% and 46% of a
Inducing emesis is of limited use because of the rapid
given dose is excreted unchanged in the urine (Cochin
absorption of phencyclidine, but may be attempted in
et al., 1950). The mescaline molecule is structurally simi-
very recent ingestions of large doses if no contraindica-
lar to serotonin and acts on the 5-HT 2A receptor (Nichols,
tions exist (Kisseberth and Trammel, 1990). Activated
2004).
charcoal binds phencyclidine, prevents recycling, and is
Clinical signs of mescaline intoxication in dogs
reported to reduce mortality in dogs and rats. Repeated
include vomiting, mydriasis, injection of the conjunctiva,
dosing of activated charcoal is recommended because of
hyperreflexia, chewing motions of the jaw, excitation and
enterohepatic cycling. Forced diuresis with mannitol or
disorientation, or sometimes profound depression. Dogs
furosemide will increase the rate of clearance. Urinary
are reported to recover from severe depression within
acidification enhances excretion but is contraindicated in
10 h (Cochin et al., 1950). Symptoms in humans are fairly
the presence of acidosis or rhabdomyolysis. Electrolyte
similar and may include emesis, especially after ingestion
abnormalities and hypoglycemia should be corrected as
of Echinopsis spp. (Halpern, 2004). Other symptoms that
necessary.
have been reported are mydriasis, sweating, hallucina-
Cardiorespiratory abnormalities have been reported in
tions, synesthesia, disorientation, incoordination,
some species. Muscle rigidity, hyperactivity, and seizures
increased heart rate and blood pressure, and hyperthermia.
associated with ketamine have been treated successfully
with diazepam. Severe seizures require barbiturates or
general anesthesia. The body temperature of the patient Salvia divinorum
must be closely monitored.
S. divinorum, known as salvia, is a perennial sage closely
related to mint. The plant is native to Mexico and grows
Other Compounds in humid, semitropical climates. It is cultivated in
California and Hawaii (Anonymous, 2011). The plant is
Mescaline, the active compound in peyote, is a well-
of cultural significance to the Mazatec Indians of Oaxaca,
studied hallucinogen because of its significance both cul-
Mexico, where it is used to treat diarrhea, headaches,
turally and in the illicit drug trade. Salvinorin-A is an
rheumatism, and semimagical diseases (Prisinzano, 2005).
agent with hallucinogenic potential that is found in the
These indigenous Mexicans either chew the fresh leaves
legal herb S. divinorum.
or extract the juice. Salvia is also smoked (Frohne and
Pfa ¨nder, 2005; Prisinzano, 2005). Salvia is a controlled
Mescaline substance in parts of Europe and the United States.
Use of mescaline (3,4,5-trimethoxyphenethylamine) dates Salvia contains various diterpenes, including salvinor-
back to approximately 8500 BC (Bruhn et al., 2002). It is ins A through F and divinatorins A through C. Similar
derived from several species of cactus including compounds are present in plants of the genus Coleus.
Lophophora williamsii, the peyote Echinopsis pachanoi, Biological effects are attributed to salvinorin-A.
the San Pedro cactus, and E. peruvianus, the Peruvian Salvinorin-A is absorbed through the oral mucosa
torch cactus. The latter two cacti are native to South (Halpern, 2004). Little is known about the metabolism of
America and are common ornamental plants. Both can be this compound, but the elimination half-life in nonhuman