I ordered some from ebay (supposedly 100% pure) that had no nauseous effect (wasn't advertised as fish P)
The fish P from ebay made me nauseous a couple times and then once the nausea got so bad I just hurled all over the sink.
I don't remember the brand - I got disgusted and tossed it.
I'm pretty sure there must have been some sort of additive.
I've tried several meds from ebay and vet supply stores and that was the one that affected me in that way.
How has the fish P been working for you?