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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

xylitol - treatment

gastric decontamination
monitor bloog glucosse levels - often become hypoglycaemic
dextrose for sugar levels + hepatotoxicity