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- Topic: TOAD TOXINS
-
- 0.0 OVERVIEW
- 0.1 LIFE SUPPORT
- This overview assumes that basic life support measures
- have been instituted.
- 0.2 CLINICAL EFFECTS
- 0.2.1 SUMMARY
- A. There are several types of toxic substances found in
- toads, including cardioactive agents, catecholamines,
- indolealkylamines and non-cardiac sterols. These toxins
- are located in the skin and parotid glands and may be
- transferred by handling or ingesting a toad's skin.
- 0.2.3 HEENT
- A. Secretions of the toad parotid glands will cause pain
- and severe irritation when placed in eyes, nose, and
- throat.
- 0.2.4 CARDIOVASCULAR
- A. Dogs who have been poisoned with bufagins develop
- ventricular fibrillation and symptoms resembling
- digitalis poisoning. Vasoconstriction may also be seen.
- 0.2.5 RESPIRATORY
- A. Dyspnea and weakened respirations may be seen.
- 0.2.6 NEUROLOGIC
- A. Paralysis and seizures have been reported in both humans
- and animals. Many bufagins have local anesthetic
- actions, especially on the oral mucosa.
- 0.2.7 GASTROINTESTINAL
- A. Salivation and vomiting were often seen in animals.
- These toxins may cause numbness of the oral mucosa if
- ingested.
- 0.2.14 HEMATOLOGIC
- A. Cyanosis has been seen in poisoned dogs.
- 0.2.18 PSYCHIATRIC
- A. HALLUCINATIONS: Drug users have been known to smoke the
- chopped skins of toads for their hallucinogenic effect.
- 0.3 LABORATORY
- A. No toxic levels have yet been established for any of the
- bufagins. Since many of the other substances are
- metabolized rapidly, laboratory analysis is impractical.
- 0.4 TREATMENT OVERVIEW
- 0.4.1 SUMMARY
- A. There are three primary areas of toxicity, the first
- involving cardiac glycoside effects, the second, the
- pressor effects, and the third, the hallucinogenic
- effects. Usually the cardiovascular effects are the
- most prominent. Treatment is directed at prevention of
- absorption, and monitoring for EKG effects and
- hyperkalemia. Lidocaine, a transvenous pacemaker, and
- cholestyramine have all been used to treat digitalis-
- like poisonings. FAB fragments have not been reported
- to be of use in toad poisoning.
- B. Hemodialysis has been ineffective in removing cardiac
- glycosides.
- 0.5 RANGE OF TOXICITY
- A. The skin of one toad is sufficient to cause significant
- symptoms and even death in both animals and humans.
- Topic: TOAD TOXINS
-
- B. No toxic serum or blood levels have yet been established.
- 1.0 SUBSTANCES INCLUDED
- 1.1 THERAPEUTIC/TOXIC CLASS
- A. There are several types of toxic substances found in the
- venom of toads.
- 1. CARDIOACTIVE SUBSTANCES: Bufagins (bufandienolides) are
- cardioactive substances found in toad venom. They have
- effects similar to the cardiac glycosides found in
- plants. Bufotoxins are the conjugation products of the
- specific bufagin with one molecule of suberylargine
- (Chen & Kovarikova, 1967). Bufotoxins were originally
- isolated from the parotoid glands of toads, but have
- since been seen in various plants and mushrooms
- (Siperstein et al, 1957; Lincoff & Mitchel, 1977; Kibmer
- & Wichtl, 1986).
- 2. CATECHOLAMINES: There are also several catecholamines
- in toad venom. Epinephrine has been found in as high a
- concentration as 5% in the venom of several species.
- Norepinephrine has also been found (Chen & Kovarikova,
- 1967).
- 3. INDOLEALKYLAMINES: Chemicals found include several
- bufotenines. Bufotenines are organic bases containing
- an indole ring and have primarily oxytocic actions and
- often pressor actions (Palumbo et al, 1975). Specific
- substances include bufothionine, serotonin,
- cinobufotenine, bufotenine, and dehydrobufotenine (Chen
- & Kovarikova, 1967). Bufotenine is the 5-hydroxy
- derivative of N,N,dimethyltryptamine and is a
- hallucinogen (Gilman et al, 1985).
- 4. NONCARDIAC STEROLS: The sterols found in toad venom
- include cholesterol, provitamin D, gamma sitosteral, and
- ergosterol. They do not appear to have a significant
- role in toxicity (Chen & Kovarikova, 1967; Palumbo et
- al, 1975).
- 1.3 DESCRIPTION
- A. Toads known to contain toxins include:
- 1. Bufo alvarius
- 2. Bufo americanus
- 3. Bufo arenarum
- 4. Bufo asper
- 5. Bufo blombergi
- 6. Bufo bufo
- 7. Bufo bufo gargarizans
- 8. Bufo formosus
- 9. Bufo fowerii
- 10. Bufo marinus
- 11. Bufo melanostictus
- 12. Bufo peltocephalus
- 13. Bufo quercicus
- 14. Bufo regularis
- 15. Bufo valliceps
- 16. Bufo viridis
- 1.4 GEOGRAPHICAL LOCATION
- A. Toads are found throughout the world, Bufo marinus having
- one of the widest distributions.
- Topic: TOAD TOXINS
-
- 2.0 CLINICAL EFFECTS
- 2.1 SUMMARY
- A. Poisoning by toad toxins is primarily a problem with
- animals and may be fatal (Perry & Bracegirdle, 1973).
- There have been fatalities in Hawaii, Phillipines, and
- Fiji occurring after eating the toads as food (Tyler,
- 1976; Palumbo et al, 1975). The toxins are located in
- the skin and parotid glands and may be transferred by
- handling a toad. A toad that sits in a dog's watering
- dish for some time may leave enough toxin to make the pet
- ill (Smith, 1982). The toxicity varies considerably by
- the toad species and its geographic location. The death
- rate for untreated animals exposed to Bufo marinus is
- nearly 100% in Florida, is low in Texas, and only about
- 5% in Hawaii (Palumbo et al, 1975).
- 2.3 HEENT
- 2.3.2 EYES
- A. IRRITATION: If the secretions of the toad parotid
- glands come in contact with human eyes, pain and severe
- irritation will result (Tyler, 1976; Smith, 1982).
- 2.3.4 NOSE
- A. IRRITATION: Exposure of the nasal mucous membranes to
- the toad toxins may produce severe irritation (Chen &
- Kovarikova, 1967).
- 2.3.5 THROAT
- A. The mouth and throat may become anesthetized if
- bufotoxins have been ingested (Chen & Kovarikova, 1967).
- 2.4 CARDIOVASCULAR
- A. VENTRICULAR FIBRILLATION: Dogs intentionally poisoned
- with bufagins orally develop ventricular fibrillation and
- if untreated - death (Palumbo et al, 1975). The symptoms
- resemble digitalis poisoning.
- B. VASOCONSTRICTION: Bufagins constrict arterial blood
- vessels (Chen & Kovarikova, 1967). Bufotenine itself is
- not hallucinogenic, but acts as a pressor rather than a
- hallucinogen in humans (Kantoretal, 1980).
- 2.5 RESPIRATORY
- A. DYSPNEA: Weakened respirations may be seen if toad
- toxins have been ingested (Smith, 1982).
- 2.6 NEUROLOGIC
- A. PARALYSIS: Paraplegia has been noted in toad poisonings
- of dogs and cats. Incoordination and progressive
- paralysis may be earlier symptoms (Perry & Bracegirdle,
- 1973; Smith, 1982).
- B. SEIZURES: Have been reported in poisoned dogs and a few
- cats (Palumbo et al, 1975; Chen & Kovarikova, 1967), as
- well as a 5-year-old boy (Hitt & Ettinger, 1986). Onset
- was within 5 minutes. The seizures continued unabated
- for 60 minutes.
- C. LOCAL ANESTHESIA: Many bufagins have local anesthetic
- actions, especially on the oral mucosa (Chen &
- Kovarikova, 1967).
- 2.7 GASTROINTESTINAL
- A. SALIVATION: Intense salivation is usually seen in
- poisoned cats and dogs (Perry & Bracegirdle, 1973), and
- Topic: TOAD TOXINS
-
- was seen in one 5-year-old boy (Hitt & Ettinger, 1986).
- B. VOMITING: Is often present in animals (Perry &
- Bracegirdle, 1973).
- C. NUMBNESS: If ingested, the toxins cause numbness of the
- oral mucosa (Smith, 1982; Chen & Kovarikova, 1967).
- 2.12 FLUID-ELECTROLYTE
- A. HYPERKALEMIA: Similar to that seen with digitalis
- poisoning, may be seen.
- 2.13 TEMPERATURE REGULATION
- A. FEVER: Is a symptom common to ingestion of toads by cats
- and dogs (Perry & Bracegirdle, 1973).
- 2.14 HEMATOLOGIC
- A. CYANOSIS: Has been seen in dogs (Hitt & Ettinger, 1986).
- 2.15 DERMATOLOGIC
- A. PERSPIRATION: Although handling toads is generally not
- considered seriously injurious to humans, it is thought
- to dramatically reduce perspiration (Smith, 1982).
- 2.18 PSYCHIATRIC
- A. HALLUCINATIONS: In 1971, drug users in Queensland were
- smoking the chopped skins of Bufo marinus for its
- hallucinogenic effect (Tyler 1976). Toad skin has been
- used for its hallucinogenic properties throughout the
- world (Emboden, 1979), but Bufo alvarins is the only Bufo
- species known to contain a hallucinogenic tryptamine
- (McKenna & Towers, 1984).
- 3.0 LABORATORY
- 3.2 MONITORING PARAMETERS/LEVELS
- 3.2.1 SERUM/BLOOD
- A. No toxic levels have yet been established for any of the
- bufagins. Many of the other substances are metabolized
- rapidly, and laboratory analysis would be impractical.
- 3.2.3 OTHER
- A. EKG: Patients who have had significant exposures should
- have a baseline EKG to observe for abnormalities.
- Symptomatic patients should continue to have EKGs
- performed.
- B. A serum potassium level should be drawn to test for
- hyperkalemia (Chen & Kovarikova, 1967).
- 4.0 CASE REPORTS
- A. A typical animal case report involves a dog that finds a
- slow hopping toad and mouths the animal playfully. The
- animal usually experiences immediate salivation, and
- irritation of the mucus membranes of the mouth and
- throat. If the dog eats the toad, vomiting and paralysis
- may lead to seizures and death. Animals who recover
- usually do not have significant sequelae.
- B. Although human deaths have been reported in the lay
- literature, we were able to find only one case report of
- a human death or serious intoxication in the medical
- literature. This was a 5-year-old who had mouthed a Bufo
- alvarius (Colorado River Toad) and developed status
- epilepticus successfully treated with diazepam and
- phenobarbital (Hitt & Ettinger, 1986).
- 5.0 TREATMENT
- 5.1 LIFE SUPPORT
- Topic: TOAD TOXINS
-
- Support respiratory and cardiovascular function.
- 5.2 SUMMARY
- A. There are 3 primary areas of toxicity. The first
- involves the cardiac glycoside-like effects of the
- bufagins; the second is the pressor effects of the
- catecholamines; and the third is the hallucinogenic
- effect of the indolealkylamines. After a toad had been
- ingested, it is difficult to evaluate which of these
- effects will predominate. Usually, the cardiovascular
- effects are the most prominent. The patient should be
- observed for arrhythmias and for hallucinations. There
- have been minimal human exposures, so clinical
- presentation and course are difficult to predict.
- 5.3 ORAL/PARENTERAL EXPOSURE
- 5.3.1 PREVENTION OF ABSORPTION
- A. EMESIS
- 1. Emesis may be indicated in substantial recent
- ingestions unless the patient is obtunded, comatose or
- convulsing or is at risk of doing so based on
- ingestant. Emesis is most effective if initiated
- within 30 minutes of ingestion. Dose of ipecac syrup:
- ADULT OR CHILD OVER 90 TO 100 POUNDS (40 to 45
- kilograms): 30 milliliters; CHILD 1 TO 12 YEARS: 15
- milliliters; CHILD 6 TO 12 MONTHS (consider
- administration in a health care facility): 5 to 10
- milliliters. After the dose is given, encourage clear
- fluids, 6 to 8 ounces in adults and 4 to 6 ounces in a
- child. The dose may be repeated once if emesis does
- not occur within 30 minutes.
- 2. If emesis is unsuccessful following 2 doses of ipecac,
- the decision to lavage or otherwise attempt to
- decontaminate the gut should be made on an individual
- basis. This amount of ipecac poses little toxicity of
- itself.
- 3. Refer to the IPECAC/TREATMENT management for further
- information on administration and adverse reactions.
- B. MULTIPLE DOSE ACTIVATED CHARCOAL/CATHARTIC
- 1. Cardiac glycosides and bufandienolides are adsorbed to
- activated charcoal and enterohepatic circulation may be
- decreased by multiple-dose activated charcoal (Balz &
- Bader, 1974).
- 2. Repeated oral charcoal dose (every 2 to 6 hours) may
- enhance total body clearance and elimination. A saline
- cathartic or sorbitol may be given with the first
- charcoal dose and repeated until charcoal appears in
- the stools. Do not repeat charcoal if bowel sounds
- absent.
- 3. Administer charcoal as slurry. The FDA suggests a
- minimum of 240 milliliters of diluent per 30 grams
- charcoal (Dose: Optimum dose of charcoal is not
- established; usual INITIAL dose is 30 to 100 grams in
- adults and 15 to 30 grams in children; some suggest
- using 1 to 2 grams per kilogram as a rough guideline,
- particularly in infants). REPEAT doses have ranged
- from 20 to 50 grams in adults. Doses in children have
- Topic: TOAD TOXINS
-
- not been established, but one-half the initial dose is
- recommended.
- 4. Administer a saline cathartic or sorbitol, with the
- INITIAL charcoal dose, mixed with charcoal or
- administered separately. Dose:
- a. Magnesium or sodium sulfate (ADULT: 20 to 30 grams
- per dose; CHILD: 250 milligrams per kilogram per
- dose) OR magnesium citrate (ADULT AND CHILD: 4
- milliliters per kilogram per dose up to 300
- milliliters per dose).
- b. Sorbitol (ADULT: 1 to 2 grams per kilogram per dose
- to a maximum of 150 grams per dose; CHILD: (over 1
- year of age): 1 to 1.5 grams per kilogram per dose
- as a 35 percent solution to a maximum of 50 grams
- per dose). Consider administration in a health care
- facility, monitoring fluid-electrolyte status,
- especially in children.
- 5. When used with multiple-dose charcoal regimens, the
- safety of repeated cathartics has not been established.
- Hypermagnesemia has been reported after repeated
- administration of magnesium containing cathartics in
- overdose patients with normal renal function. In young
- children, cathartics should be repeated no more than 1
- to 2 times per day. Administration of cathartics
- should be stopped when a charcoal stool appears.
- Cathartics should be used with extreme caution in
- patients who have an ileus or absent bowel sounds.
- Saline cathartics should be used with caution in
- patients with impaired renal function.
- 6. Refer to the ACTIVATED CHARCOAL/TREATMENT management
- for further information on administration and adverse
- reactions.
- C. One of the best first aid measures to prevent toxicity
- in animals is to immediately flush the oral mucous
- membranes of dogs, cats, and even people who have had
- mucous membrane exposure to decrease absorption. Do not
- swallow the rinse water.
- 5.3.2 TREATMENT
- A. CARDIAC EFFECTS
- 1. MONITOR EKG CONTINUOUSLY: For abnormal cardiac rates
- and rhythms. In patients with previously healthy
- hearts, the most common manifestation is bradycardia
- with or without varying degrees of AV block. Peaked T
- waves, depressed ST segments, widened QRS, and
- prolonged PR interval may also be noted.
- 2. HYPERKALEMIA: Hyperkalemia following acute overdose
- may be life-threatening. The emergency management of
- life-threatening hyperkalemia (potassium levels greater
- than 6.5 mEq/L) includes the intravenous administration
- of bicarbonate, glucose, and insulin. DOSE:
- Administer 0.2 units/kg of regular insulin with 200 to
- 400 mg/kg glucose (IV dextrose 25% in water).
- Concurrent administration of IV sodium bicarbonate
- (approximately 1.0 mEq/kg up to 44 mEq per dose in an
- adult) may be of additive value in rapidly lowering
- Topic: TOAD TOXINS
-
- serum potassium levels. Monitor the EKG while
- administering the glucose, insulin, and sodium
- bicarbonate. This therapy should lower the serum
- potassium level for up to 12 hours.
- 3. ATROPINE: Atropine is useful in the management of
- bradycardia, varying degrees of heart block and other
- cardiac irregularities due to the digitalis-like
- induced effects of enhanced vagal tone on the SA node
- rhythmicity and on conduction through the AV node.
- DOSE: Adult: 0.6 mg per dose IV; Child: 10 to 30
- mcg/kg per dose up to 0.4 mg per dose (may be repeated
- as needed to achieve desired effects). Monitor EKG
- carefully while administering atropine.
- 4. PHENYTOIN: Phenytoin is useful in the management of
- digitalis-like induced ventricular dysrhythmias and
- improves conduction through the AV node. Low dose
- phenytoin (Adult: 25 mg per dose IV at 1 to 2 hour
- intervals; Child: 0.5 to 1.0 mg/kg per dose IV at 1 to
- 2 hour intervals) appears to improve AV conduction.
- Larger doses are needed for the management of
- ventricular dysrhythmias: Loading Dose for adults and
- children: Administer 15 mg/kg up to 1.0 gram IV not to
- exceed a rate of 0.5 mg/kg per minute. Maintenance
- Dose: Adults - administer 2 mg/kg IV every 12 hours as
- needed; Child - administer 2 mg/kg every 8 hours as
- needed. Monitor serum phenytoin levels just prior to
- initiating and during maintenance therapy to assure
- therapeutic levels of 10 to 20 mcg/ml (39.64 to 79.28
- nmol/L). Monitor EKG carefully.
- 5. LIDOCAINE
- a. Lidocaine is useful in the management of ventricular
- tachyarrhythmias, PVC's, and bigeminy. Lidocaine does
- not improve conduction through the AV node.
- b. ADULT: BOLUS: 50 to 100 milligrams (0.70 to 1.4
- milligrams per kilogram) under EKG monitoring. Rate:
- 25 to 50 milligrams per minute (0.35 to 0.70
- milligrams per kilogram per minute). A second bolus
- may be injected in 5 minutes if desired response is
- not obtained. No more than 200 to 300 milligrams
- should be administered during a one hour period.
- INFUSION: Following a bolus, an infusion at 1 to 4
- milligrams per minute (0.014 to 0.057 milligram per
- kilogram per minute) may be used. PEDIATRIC: BOLUS:
- 1 milligram per kilogram. INFUSION: 3 micrograms per
- kilogram per minute.
- 6. TRANSVENOUS PACEMAKER: Insertion of a transvenous
- pacemaker should be considered in those patients with
- severe bradycardia and/or slow ventricular rate due to
- second degree AV block who fail to respond to atropine
- and/or phenytoin drug therapy.
- 7. FAB FRAGMENTS: Have not been documented to be of any
- value in the treatment of bufagins. Cross reactivity
- has not been proven.
- 8. CHOLESTYRAMINE: Digitoxin (and theoretically bufagins)
- elimination appears to be enhanced by the serial
- Topic: TOAD TOXINS
-
- administration of cholestyramine, 4 grams orally every
- 6 hours. Cholestyramine appears to have minimal effect
- on absorption and excretion of cardiac glycosides in
- man.
- 9. One 5-year-old boy did well on high-dose hydrocortisone
- sodium succinate and phenobarbital (Hitt & Ettinger,
- 1986).
- B. ANIMALS (ESPECIALLY DOGS) (Palumbo et al, 1975):
- 1. ATROPINE: May be used to decrease secretions and block
- vagal effects. It is not a specific antidote.
- 2. ANTIHISTAMINES OR CORTICOSTEROIDS: May reduce the
- effects of bufotoxins on the mucous membranes of the
- mouth and other organs, but have little direct action.
- 3. PENTOBARBITAL-INDUCED ANESTHESIA: Does increase canine
- tolerance to toad venom intoxication.
- 4. PROPRANOLOL: Has been tried on canines, with some
- success. The dose used was high: 5 mg/kg.
- 5.3.3 ENHANCED ELIMINATION
- A. MULTIPLE DOSE ACTIVATED CHARCOAL: May be of some use.
- It has been used after IV administration of methyl
- proscillaridin (Belz & Bader, 1974).
- B. HEMODIALYSIS: Has been ineffective in removing cardiac
- glycosides but may assist in restoring potassium to
- normal levels. It has yet to be tried on bufagins.
- 5.6 DERMAL EXPOSURE
- 5.6.1 DECONTAMINATION
- A. Wash exposed area extremely thoroughly with soap and
- water. A physician may need to examine the area if
- irritation or pain persists after washing.
- 5.6.2 TREATMENT
- A. Effects may be seen after dermal exposure. Treatment
- should be as appropriate under the oral treatment
- section.
- 6.0 RANGE OF TOXICITY
- 6.2 MINIMUM LETHAL EXPOSURE
- A. The skin of one toad is sufficient to cause significant
- symptoms and even death in both animals and humans.
- 6.4 TOXIC SERUM/BLOOD CONCENTRATIONS
- A. No toxic serum or blood levels have yet been established.
- 6.6 LD50/LC50
- A. TABLE I - BUFAGIN LETHAL DOSES IN CATS
- NAME Mean (Geo.)
- LD,, mg/kg
- Arenobufagin 0.08
- Bufotalin 0.13
- Desacetylbufotalin 0.26
- Cinobufagin 0.20
- Acetylcinobufagin 0.59
- Desacetylcinobufagin inactive
- Cinobufotalin 0.20
- Acetylcinobufotalin 0.18
- Desactylcinobufotalin inactive
- Marinobufagin 1.49
- Acetylmarinobufagin 0.95
- 12Beta-Hydroxymarinobufagin 3.00
- Topic: TOAD TOXINS
-
- Bufotalidin (hellebrigenin) 0.08
- Acetylbufotalidin 0.06
- Resibufogenin inactive
- Acetylresibufogenin inactive
- 12Beta-Hydroxyresibufogenin 4.16
- Bufalin 0.14
- Telocinobufagin 0.10
- Bufotalinin 0.62
- Artebufogenin inactive
- Gamabufotalin 0.10
- Vallicepobufagin 0.20
- Quercicobufagin 0.10
- Viridobufagin 0.11
- Regularobufagin 0.15
- Fowlerobufagin 0.22
- B. TABLE II BUFOTOXIN LETHAL DOSES IN CATS
- NAME Mean (Geo.)
- LD, mg/kg
- Viridobufotoxin 0.27
- Vulgarobufotoxin 0.29
- Cinobufotoxin 0.36
- Gamabufotoxin 0.37
- Arenobufotoxin 0.41
- Marinobufotoxin 0.42
- Regularobufotoxin 0.48
- Alvarobufotoxin 0.76
- Fowlerobufotoxin 0.79
- C. REFERENCE: (Chen & Kovarikova, 1967).
- 6.8 OTHER
- A. The structure of the cardioactive bufadienolides leads to
- greater potency than the corresponding plant glycosides
- thus the cardenolides of plants - digitoxigenin,
- periplogenin, oleandrigenin, sarmentogenin, and
- strophanthidin, corresponding to bufalin,
- telocinobufagin, bufotalin, gamabufotalin, and
- bufotalidin - have lower toxicities.
- B. The toxicity of the cardioactive bufotoxins is lower than
- those of the corresponding bufagins (bufadienolides)
- (Chen & Kovarikova, 1967).
- C. The skin of Bufo alvarius contains 5-methoxy-N,N-
- dimethyltryptamine (5-MeO-DMT) at a concentration of 50
- to 160 mg/g of skin (Daly & Witkop, 1971).
- 7.0 AVAILABLE FORMS/SOURCES
- A. BUFOTOXINS: Is the name of a collection of compounds
- found in the toad venom which may be secreted into toad
- skin or found in 2 glands behind the eyes, called parotid
- glands (Tyler, 1976). Bufotoxins may also be
- specificially applied to the conjugates of a bufagin with
- suberylargine.
- B. Before digitalis was extracted from Digitalis purpura,
- dried and powdered toad skins were used as a cardiac
- medication (Burton, 1977). Other "folk" uses include
- expectorant, diuretic, and remedy for toothaches,
- sinusitis, and hemorrhage of the gums.
- C. Toad skins have also been used for their hallucinogenic
- Topic: TOAD TOXINS
-
- effect (Emboden, 1979).
- 8.0 KINETICS
- 8.1 ABSORPTION
- A. The oral absorption of the bufagins and bufotoxins is
- generally poor. Less than 15% of cinobufagin is absorbed
- orally in rats.
- B. Other components of toad venom are rapidly absorbed via
- mucous membranes and cause immediate symptoms in animals
- (Smith, 1982).
- 8.4 EXCRETION
- 8.4.3 BILE
- A. Little could be found concerning the excretion of these
- compounds; similar cardenolides and substances such as
- proscillaridin are excreted largely in the bile (Belz &
- Bader, 1974).
- 9.0 PHARMACOLOGY/TOXICOLOGY
- 9.1 PHARMACOLOGIC MECHANISM
- A. Most bufandienolides are cardiotonic sterols synthesized
- by toads from cholesterol (Siperstein, 1957). The
- lactone ring is 6-membered of an alpha pyrone type
- attached to C17. They have a secondary hydroxy group at
- C3 and are called bufagins - which corresponds to the
- aglycones found in the cardiac glycosides in plants.
- None of these bufandienolides conjugates with a
- carbohydrate (as do the plants) to form glycosides, but
- some do form bufotoxins by combining with suberylargine
- (Chen & Kovarikova, 1967).
- B. In the toad, some of these compounds (eg, resibufogenin)
- are ouabain-like and increase the force of contraction of
- heart muscle (Lichtstein et al, 1986).
- C. The pharmacology of the catecholamines found in toad
- venom is well known and need not be discussed here.
- D. INDOLEALKYLAMINES: Pharmacology is also known. Besides
- having some hallucinogenic effects, these compounds may
- stimulate uterine and intestinal muscle (Chen &
- Kovarikova, 1961).
- 9.2 TOXICOLOGIC MECHANISM
- A. Bufagins and bufotoxins have been shown to inhibit
- sodium, potassium, ATPase activity (Lichtstein et al,
- 1986). Their action is almost the same as that of the
- digitalis glycosides (Palumbo et al, 1975).
- 12.0 REFERENCES
- 12.1 GENERAL REFERENCES
- 1. Belz GG & Bader H: Effect of oral charcoal on plasma
- levels of intravenous methyl proscillaridin. Klin
- Wochenschr 1974; 52:1134-1135.
- 2. Burton R: Venomous Animals: Colour Library International
- Ltd. London, 1977.
- 3. Chen KK & Kovarikova A: Pharmacology and toxicology of
- toad venom. J Pharm Sci 1967; 56:1535-1541.
- 4. Daly JW & Witkop B: Chemistry and pharmacology of frog
- venoms. In: Bucherl W & Buckly EE (eds). Venomous
- Animals and Their Venoms, vol 2, Academic Press, New York,
- 1971.
- 5. Emboden W: Narcotic Plants. MacMillan Publishing Company,
- Topic: TOAD TOXINS
-
- Inc, 1979.
- 6. Gilman AG, Goodman LS, Rall TW et al: The Pharmacological
- Basis of Therapeutics, 7th ed. MacMillan Publishing
- Company, 1985.
- 7. Gould L, Solomon F, Cherbakoff A et al: Clinical studies
- on proscillaridin, a new squill glycoside. J Clin
- Pharmacol 1971; 11:135-145.
- 8. Hitt M & Ettinger DD: Toad toxicity. N Engl J Med 1986;
- 314:1517.
- 9. Kantor RE, Dudlettes SD & Shulgin AT: 5-Methoxy-a-methyl-
- tryptamine (a, O-dimethylserotonin), a hallucinogenic
- homolog of serotonin. Biological Psychiatry 1980;
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- 13.0 AUTHOR INFORMATION
- A. Written by: David G. Spoerke, M.S., RPh., 06/86
- B. Reviewed by: Ken Kulig, M.D., 06/86
- C. Specialty Board: Biologicals
- D. In addition to standard revisions of this management
- certain portions were updated with recent literature:
- 11/86.
- THIS FILE IS FROM THE ONE AND ONLY
- __ __ ______________________ ______________
- / \\ /.~\ /__ __/ ~/ __ ~\/ ~/ ~\ INDEPENDANT
- //|:\\ // /\\_/. /\/ _/\___/. // / _/\__/ . / \ -=FOREVER=-
- / . \\ // / / / /./_ / \ // _ _/ . _/ \/ / / /\
- /. |. \/. / / / /// ____ /╖ / / / ____/ / / /// 2 Nodes
- // || // /_/_/ /./ / / / ╖ / ///| Ringdown
- /_____|__/_______\__///______ /___/ /________/________/ / :14.4/1.5Gigs
- Y________\________\__/_______/\__/___/\_______/_________\/; .206-652-3086
- : _____ _____ ______ /\____ ____\__\/ _________ /\____ ________________
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- _/____//____//__/__\_____|° /____/___//____/___/_____|° /__/_/__/_ °/_ ~/
- \________________________ /_________________________ ./_________/ __/░/
- =_*_=_°_Y_░_ _╖_°_╖_=_*_╖\/_°_=_╖_=_╖_=_°_=_╖_=_°_*_=\/_=_Y_°__=_*_=_╖/
- ~ ~ Y ~ | ~ Y ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ | ~~ ~ ~ Y ~
- | : : Th0usands&ThousaNds Of tExt fIleS >OnLine< ; |
- This file has been for educational and informational purposes only
- ; . Sysops- Mescalito Ted & Datura . ;
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