Poisoning and Herbs Flashcards
Random Poisoning Facts
55% of poisonings are from INCIDENTAL EXPOSURE; 9.6% actual suicides
Most common drugs that cause poisonings are ANALGESICS –> Sedative/Hypnotics (MOST FREQUENT and FASTEST RISING); Digoxin; Opioids
Most important issue is TIMING –> Isoniazid, TCAs, Antidepressants, Nictoine have RAPID effects
Acetaminophen, Hydrofluoric Acid, Ethylene Glycol have DELAYED onsets
WEIGHT of individual very very important
Quick Poisoning Treatments
ACTIVATED CHARCOAL –> binds to the drug in the GI tract so that it can be expelled in the FECES
IPECAC SYRUP – not used much anymore; induces vomiting; empties only 30% of the stomach contents and its administration prevents the use of activated charcoal (will just throw up); can be abused
KNOWN ANTIDOTES
Acetaminophen - N-ACETYL-CYSTEINE
Cyanide – HYDROXYCOBALAMINE
CO –> Oxygen
Digoxin –> FAD Fragment (immunologically sticks to it in the blood)
Ethylene Glycol/Methanol –> FOMEPAZOLE
Opioids –> NALOXONE
Organophosphates/Nerve Agents –> ATROPINE
What do acids and bases do when ingested?
ACIDS –> exposure causes COAGULATION NECROSIS, an ESCHAR, MINIMAL TISSUE PENETRATION
BASES –> Exposure will cause LIQUEFACTIVE NECROSIS, SAPONIFICATION, DEEEEEEP TISSUE PENETRATION
Hydrofluoric Acid
Used in glass etching, computers, automotive and air conditioner cleaners, etc
may not cause burning/itching, but can be a DELAYED PAIN REACTION
WEAKLY corrosive, but will cause injury by penetrating whatever tissue it contacts
If ingested, it can cause LOCAL and SYSTEMIC ABSORPTION OF CALCIUM
Binds Ca++ very strongly, can get into bones, and cause DEATH by binding up ALL the calcium in the body
TREATMENT? LOTS OF CALCIUM!!!!
Cleaning Agent exposure
Lots of cleaning agents have chlorine, bleach, ammonia – VAPORS when MIXED
Vapors can be very irritative to the airways, and cause STATUS ASTHMATIUS (acute severe asthma) as well as DELAYED PULMONARY INJURY!!!
CO Exposure
Binds Hb with much greater affinity than oxygen!
So no oxygen can bind at one site, and the other ones are too tightly held! NO RELEASE OF OXYGEN TO TISSUES
Also inhibits CELLULAR RESPIRATION
Formed by the incomplete combustion of carbon material (car exhaust, ventilation of a heater blocked, etc)
No O2 to tissues –> BRAIN and HEART most affected
Symptoms of CO Exposure
Flu like illness with NO FEVER (mild)
Cherry Red appearance (high exposure)
DELAYED NEUROLOGICAL SEQUELAE and COGNITIVE EFFECTS
Those with higher metabolic rates (kids) are actually WORSE OFF
Treatment of CO exposure
OXYGEN OXYGEN OXYGEN!!!!!!!
Hyperbaric O2 Chamber best
CO detectors are a must
LEAD exposure
Pervasive toxin in the environment
Found in smelting, construction, demolition materials, folk medicines, cosmetics, bullets, etc etc etc
Most poisoning is ASYMPTOMATIC, but can have systemic effects at high doses
CNS effects –> hyperIRRITABILITY, intermittent LETHARGY, COGNITIVE IMPAIRMENT –> with several poisonings –> LEAD ENCEPHALOPATHY
PNS effects –> Peripheral NEUROPATHY; WRIST and FOOT DROP
N/V, abdominal pain, anorexia, microcytic anemia, possible impaired hearing/growth and IMPAIRED COGNITION and BEHAVIORAL CHANGES in KIDS –> BIGGEST CONCERN!!! Affects arborization of the brain neurons
BASOPHILIC STIPPLING = DIAGNOSTIC
Treating Lead Poisoning
Oral Succimer Therapy
Calcium Disodium EDTA
BAL (Dimercaprol)
PENICILLAMINE (side effects in 1/3)
Life threatening encephalopathy? BAL and THEN Calcium EDTA (in that order)
Calcium alone or before is so effective that it will literally pull our calcium out of us –> bone and brain too –> SEIZURES –> Give BAL first and this will be prevented
Alcohol Poisoning
Main concern is the MAINTENANCE OF AN AIRWAY
Alcohol Depresses respiratory function - patient may either stop breathing or aspirate vomit while passed out
CHILDREN CAN BECOME SEVERELY HYPOGLYCEMIC REALLY FAST FROM ALCOHOL POISONING because of decreased GLYCOGEN stored in the liver
Problem with weed/bug killers?
Most contain ORGANOPHOSPHATES –> these are ACETYLCHOLINESTERASE INHIBITORS –> poisoning with these guys will send a person into CHOLINERGIC OVERDRIVE –> “Wet Symptoms” –> Salivation, lacrimation, urination, GI upset, Diarrhea, Emesis, Fluid in the lungs
TREATMENT with ATROPINE!!!!! Then we can use PRALIDOXIME which will regenerate AChE
First symptoms of IRON TOXICITY?
BLOODY VOMIT, BLOODY DIARRHEA
Iron destroys the intestinal barrier that keeps it from crossing into the bloodstream
TCA Poisoning
Manifests as CV TOXICITY (Na channel block –> widening of QRS –> unremitting v tach, Torsades, V fib, death)
ANTICHOLINERGIC side effects (DRY symptoms – mydriasis, tachycardia, urinary RETENTION, decreased GI, dry mouth, etc
NEURO SYMPTOMS –> Seizures
Treating TCA Overdose?
NO GOOD ANTIDOTE!!!!
Main treatment is AGGRESSIVE decontamination with ACTIVATED CHARCOAL
If CV symptoms have started, give Sodium Bicarb to compete with Na Channel Block
Problem with VERAPAMIL?
Calcium Channel Blocker –> VERY dangerous in OD –> once it is absorbed, the constellation of symptoms include BRADYCARDIA, HYPOTENSION, MENTAL STATUS CHANGES
Treatment? No good treatment!! Can give calcium!
Snake Bites?
Not all are poisonous, but if one is, expect to see the area as SWOLLEN, DISCOLORED, OOZING
Treat with CROFAB –> antibody that binds the venom in the blood and stops the progression of symptoms from that point on
Drugs made from HERBS
• Opiates –> come from Papaver Somniferum
• Digoxin –> from D. lanta
• Lidocaine –> from Erythroxylum coca
• Warfarin –> from Melilotus officinalis
o Discovered when cows suddenly began dying due to hemorrhagic disease (bleeding from the ears/nose)
o Warfarin can be reversed by VITAMIN K since it is a Vitamin K antagonist and the newer drugs from anticoagulants cannot be reversed
• Progestin –> from Diascorea villosa
• Cromolyn –> from Ammi visnaga
• Cancer Drugs
o Etoposide and Tenoposide –> from Podophyllum peltatum (poisonous) o Vincristine and vinblastine –>from Catharanthus roseus
o Paclitaxel –> from Taxus brevifolia
Aconite
Can cause arrhythmias, muscle paralysis
Used for treatment of CV conditions, also a sedative
Pyrrolizidine Alkaloids
SATURATED PAs are NOT TOXIC
UNSATURATED ARE TOXIC!!!!!! Specifically harmful to LIVER and LUNGS –> found it COLTSFOOT (for cough), BORAGE and COMFREY, which is found in some teas
Rue and Pennyroyal
Abortificants
Can cause MULTI-ORGAN FAILURE
Penny can also cause coagulopathy, metabolic acidosis, seizures
HERB most involved in DRUG interactions?
ST. JOHN WORT
Most common DRUG in Herb-Drug interactions?
WARFARIN!!!!!!
