Symptomatic therapies are the mainstay of treatment
Antiemetics and IVF
Atropine for bradycardia
Mannitol - Recommended by several experts for neurologic symptoms if given within 24-48 hours of onset . However, no benefit over normal saline in RCT
Caution: patients may be hypovolemic due to vomiting/diarrhea and should be appropriately volume resuscitated prior to considering mannitol
Amitriptyline reported effective for neuropathic pain in several case series 
Gabapentin and Pregabalin  also reported to control neurologic symptoms
Prevent recurrences - instruct patient to not ingest alcohol, caffeine, nuts or fish for 6 months
Antiemetics and IVF
Atropine for bradycardia
Caution: patients may be hypovolemic due to vomiting/diarrhea and should be appropriately volume resuscitated prior to considering mannitol
Ciguatera
Toxins
Camphor toxicity
Kratom toxicity
Scombroid
Monkeypox
Tetrodotoxin 
Toxic alcohols