Studies suggest that the toxic dose of CBD in humans would be around 20 000 mg in a single dose. This is equivalent to roughly 13 - 200 bottles of oil depending on the amount and concentration. However, even such a dose would most likely not be fatal.
However, in combination with certain drugs, side effects can occur that could be severe depending on the dose and severity of the disease.
The UK Food Standards Agency requires a maximum dose of 70 mg CBD/day to be stated on CBD packets for consumption.