A coroner questioned the regulation of online pharmacies after a woman died as a result of her addiction to the painkiller codeine.
Debbie Headspeath, 41, collapsed at home in Ipswich in 2017.
The inquest heard she had been prescribed the opiate for back pain by her GP in 2008 and had later bought more online without his knowledge.
The Suffolk Coroner said he would ask the government to look at closing "regulatory gaps" in the system.
The inquest found Mrs Headspeath died from pneumonitis caused by acute pancreatitis which in turn was caused by chronic codeine use.
An investigation by the coroner's office found she had been prescribed codeine from 16 online companies spending more than £10,000 - on top of her prescriptions from her local NHS surgery.
Family 'let down'
Her GP, Dr Peter Burn of the Two Rivers practice, told the inquest he felt she had been honest about her dependence, but had been reluctant to fully engage with drug addiction agencies.
He said he was not aware of her use of online chemists, but he had kept prescribing codeine to stop her taking over-the-counter ibuprofen and she had had 120 appointments with them between 2014 and 2017 as they worked towards weaning her off the drug.
Coroner Nigel Parsley said Mrs Headspeath had been able to "manipulate" the system and he delivered a narrative conclusion that she died as a result of the "uncoordinated availability of codeine from multiple suppliers".
Mrs Headspeath's mother Elaine Gardiner said the family felt "let down" and it was "disgraceful" there was no system where online firms were legally obliged to check with a patient's local GP.
The coroner said he would prepare a full prevention of future deaths report for the family and Department of Health.