Flashcards in Toxicology Deck (29):
1
paracetamol
v.dangerous to cats - lack metabolic capacity to detoxify paracetamol
Toxicity occurs via saturation of metabolic pathways
Toxic metabolite conjugated by glutathione
Glutathione promptly depleted
2
paracetamol toxicity - clinical signs - early <4h
Progressive cyanosis
Brown/Blue mucous membranes
Weakness & lethargy
3
paracetamol toxicity - clinical signs - 4-24h
Facial & Paw Oedema
Vomiting
Depression
Dark brown blood ‐ Methaemoglobinemia
4
paracetamol toxicity - clinical signs - the days after
Severe Methaemoglobinemia
Hepatic necrosis
5
paracetamol ‐ Methaemoglobinaemia
blue or brown mucousmembranes
arterial blood is chocolatebrown in colour and remains
dark on aeration
Cyanosis fails to respond to oxygen therapy
6
paracetamol ‐ treatment
Emesis (vomiting)
Dogs: Apomorphine
Cats: Xylazine
Activated Charcoal
Antidote: Acetylcysteine (Parvolex ®)
Precursor of glutathione
7
paracetamol - monitoring
1 week
liver function
blood clotting
renal function
total blood count
8
NSAIDs - clincal signs - early
Gastrointestinal erosion, ulceration and possibly
perforation.
Vomiting and diarrhoea (both may be bloody).
Rarely CNS symptoms (ataxia, lethargy, drowsiness)
9
NSAIDs - clincal signs - late
Renal failure
Hepatic impairment
10
NSAIDs - treatment
emesis
activated charcoal
gastric ulcer prevention - H2 receptor antagonists, Proton pump inhibitors, Ulcer healing / coating agent
Prostaglandin supplementation
Maintenance of renal function
11
theobromine (chocolate) - clinical signs
Vomiting, diarrhoea, polydipsia, salivation ‐ dehydration
CNS / Myocardial stimulation - tremor, convulsions, tachycardia, hypertension ‐ arrhythmia
Renal failure
Fatal cases – severe convulsions / circulatory failure
12
theobromine (chocolate) - treatment
Emesis ‐ Apomorphine
Repeat dose activated charcoal
Adequate rehydration
Surgery observation
monitor vital signs
13
Tremorgenic Mycotoxins
Mycotoxins are fungal metabolites produced by mould type fungus
found in mould food products/rubbish
14
Tremorgenic Mycotoxins - clinical signs
Vomiting, ataxia, whole‐body muscle tremors, rigidity with hyperextension of extremities, hyperactivity, hyperaesthesia, tachycardia, panting, tachypnoea, nystagmus and blepharospasm.
15
Tremorgenic Mycotoxins - severe cases
severe tremors and opisthotonus, convulsions and coma with
paddling. Rarely aspiration
Incr muscular activity ‐ hyperpyrexia, exhaustion, rhabdomyolysis,
dehydration and hypoglycaemia.
raised LDH, CK and liver enzymes.
16
Tremorgenic Mycotoxins - treatment
decontamination - emesis + gastric lavage
anticonvulsants
Supportive care – rehydration, cooling measures, ventilation, antiemetics
17
allium spp.
leeks, onions, shallots, spring onions, garlic & chive
forms heinz bodies in RBC - these are removed from circulation - anaemia
18
allium spp. - clinical effects
GIT - vomiting, inappetance
Heinz body anaemia - lethargy, pale MM, tachycardia & tachypnoea
Haematuria and haemoglobinurea
Methaemoglobinaemia
severe cases, icterus due to haemosiderin(high iron stores) in the liver
19
allium spp. - treatment
Emesis
AC
Monitor haematological parameters
IV fluids
Anti‐emetics if needed
20
Anticoagulant Rodenticides - clinical effects
clinical signs rare
Main effect is haemorrhage
May present with signs of dyspnoea, lethargy, weakness/anorexia
Bruising, bleeding from gums, nose, GI tract and wounds
21
Molluscicides – Metaldehyde ‐ Clinical Effects
Hypersalivation, vomiting, diarrhoea, ataxia, panting, tremors,
convulsions, hyperthermia
Tachypnoea, dyspnoea, hyperventilation and respiratory
depression
Tachycardia or bradycardia
fatalities due to resp failure
22
European adder - clinical effects
Hypovolaemia and local oedema
Local haemorrhage (rare)
Cardiac effects
Renal impairment
23
European adder - systemic effects
Shock, collapse and hypotension can occur rapidly.
Pain, panting, hypersalivation, mental status changes, hyperthermia, bruising, pale mucous membranes, tachypnoea and lameness
Coagulopathy – Anaemia, thrombocytopenia, leucocytosis, disseminated intravascular coagulation (DIC) and haematuria.
Renal effects
Hepatic effects – mild/ moderate
Cardiac effects ‐ due to myocardial damage occur with or without ECG abnormalities
24
European adder - treatment
antivenom
BP, Pulse, respiration, temperature
ECG (arrival, 12hrs & 24hrs)
BT ‐ Check for coagulopathy
Renal & hepatic parameters
can also give - analgesia, antibiotics, antihistamines
25
Cycads spp
small ferns looking plants
1-2 seeds can cause toxicity/death in dogs
26
cycads spp - clinical effects
Vomiting, haematemesis, diarrhoea, dehydration, abdominal discomfort
Hepatocellular necrosis with raised liver enzymes, hypoproteinaemia, jaundice and secondary cholestasis.
In severe cases coagulopathy, thrombocytopenia and ascites.
27
cycads spp - treatment
Emesis + RDAC
Rehydration + Anti-emetics if required
Gastroprotectants
monitor haematology
Vitamin K1 - hyprothrombinaemia.
28
xylitol
natural sugar
causes potent insulin release in dogs
liver damage
29