not to be confused with [[Marine Envenomation]]
#TOXINology
see: [Dunn Toxic Marine ingestions](x-devonthink-item://E10909BD-9785-4ABB-9BB0-DCFEFBFE76BA)
# Ciguatera poisoning
- commonest marine poisoning
- *gamberidiscus toxicus dinoflagellates* produce **ciguatoxin** (a neurotoxin)
- passes up food chain → algae → fish → consumed by humas
- coral trout, barracuda, spanish mackerel
- usually in Queensland
*Ciguatoxin*
- not inactivated by cooking or freezing, ∴ outbreaks may occur inland
- binds to voltage-sensitive Na channels causing prolonged opening → Na influx → depolarisation
- effects neurons, skeletal muscle, cardiac tissue
- most effects in neurotoxin
- **no antitoxin**
**effects**
- 4-6 hours following ingestion of fish
- GIT -- nausea, vomiting, diarrhoea , abdo pain
- next neuro sx
- myalgias, paraesthesias (numb lips and limbs), cold allodynia
- pruritis, rash
- sweating, myalgias, arthralgias, muscle cramps, bizarre taste
**management**
- supportive and symptomatic care
- IVF if dehydration
- antihistamines for pruritis
- no charcoal
- not for mannitol (outdated treatment)
**dispo**
- symptoms usually 2-5 days
- most disease mild and self-limited
- generally fully-recover in 2 weeks
- sensory disturbances may persist weeks - months
# Shellfish poisoning
- paralytic shelfish poisoning : saxitoxin
- amnestic shellfish poisioning: domoic acid
- abdo pain, cramps, confussion, memory loss, confusion
# Scrombroid poisoning
- usually consumption of tuna, mackeral
- metabolic products of bacterial degradation of blue fish flesh
- symptoms due to *histamine* release (formed from histadine when fish not preserved properly)
- similar symptoms to IgE-mediated food allergies
**assessment**
- usually 20-30 min after ingestion
- flushing
- headache, dizziness
- swelling
- nausea, vomiting
- diarrhoea
- abdo pain
- occasionally urticaria, pruritis
**management**
- mild cases no treatment
- antihistamines H1 and H2 blockers
- bronchodilators for bronchospasm
- +/- adrenaline if not sure about anaphylaxis
**dispo**
- usually self limited illness sx subsiding over 6-24 hours