The two people admitted to Salisbury District Hospital on Sunday night following an incident in the city centre have both been discharged, director of nursing Lorna Wilkinson has said.
"Given recent events, we tested both individuals for the presence of nerve agents such as Novichok. Tests on both patients came back negative," she said.
"Both patients are now medically fit and there is no need for them to be in hospital.
"While this incident did not involve nerve agents, it was still clearly very stressful for our staff who, once again, demonstrated the very best of the NHS. I want to thank them for rising to the occasion yet again."
"For reasons of patient confidentiality we will not be commenting any further."
Wiltshire Police tweeted: "The cordon that was in place outside Prezzo in Salisbury has been lifted. Thanks for your continued support and patience while our enquiries were carried out."