Brian Carney, of St Serf's Grove, Clackmannan, admitted driving whilst almost three times over the legal alcohol limit.
The 65-year-old was stopped at 10am on 24 June after police received a tip-off that he was drink driving.
However, as officers took him to Stirling police office for questioning Carney
appeared to have a mini-stroke.
He was taken to Forth Valley Royal Hospital where doctors examined him and confirmed it was a panic attack.
Sheriff Alastair Brown fined Carney £500 and banned him from the roads for 14 months when he appeared for sentence on Thursday.
Carney pled guilty to driving along Mannan Drive, Clackmannan, and other roads with 103mg of alcohol in 100ml of breath (the legal limit is 35mg).
Fiscal depute Dana Forbes explained that Carney was in the back of the police car when he had a suspected "transient
ischaemic attack" - otherwise known as a mini-stroke. An ambulance was called and treated the pensioner at the local police station before taking him to Larbert.
Ms Forbes said, "He was given further treatment at Forth Valley Royal Hospital. It appears he was having a panic attack."
She added, "He informed police he had been having a very difficult personal time and had been consuming alcohol on a daily basis."
Jim Savage, defending, said his client suffered from post-traumatic stress
disorder and depression and have been "taking comfort" in alcohol.
He had been drinking into the early hours of the morning on the day of the offence. Mr Savage added, "Alcohol has become a feature of his life and he is trying to address it."