Donna Metcalfe's post to Pure Blonde's Facebook page.
"The brewery have made contact, it was probably a gecko and they are not poisonous. I am on a health kick at the moment and weigh myself every day, so I know that my weight went down by 2kg, but I was only sick once - immediately after noticing the lizard.
"I just have been off eating and drinking - the thought of it still makes me feel ill. No more beersies for me."
Metcalfe said she'd since had a doctor's appointment, as a precaution, and hadn't had any long-term effects, "apart from the gross factor".
After the discovery she put the lid back on and put it back in the fridge. It's due to be picked up by Ministry for Primary Industries [MPI] staff today.
"Since opening the bottle and exposing the contents to air it's rapidly decomposing."
The Herald is waiting for a response from Carlton and United Breweries.