Doctors found a marijuana-filled rubber balloon up an ex-prisoner's nose 18 years after he put it there.
In the unique case, the unidentified inmate had tried to smuggle the cannabis past prison guards by inserting it into his nostril.
The 48-year-old was reportedly given the drug by his girlfriend during a visit - but had thought he'd accidentally swallowed it.
Not realising the package was stuck deep into his nose for years, a mass developed which led to him having headaches .
Years later, medics in Australia did a CT scan of his brain and that's when the discovery was made.
The BMJ Case report says: "We describe the unique case of a rhinolith that developed from a marijuana-filled balloon that the patient attempted to smuggle into a correctional facility.
"After inserting the package into his nostril, the patient then mistakenly believed it had been accidentally swallowed.
"Despite experiencing persistent symptoms of nasal obstruction and recurrent sinonasal infections, the marijuana package was only discovered 18 years after insertion following imaging for an unrelated indication."
The mass that built up in his nose was diagnosed as a marijuana-based rhinolith - a mass formed around a foreign object.
His headaches, as well as a long history of getting a blocked nose and sinus infections, are symptoms of rhinoliths, reports said.
Medics removed the 'rubber capsule' from the man's nose and his symptoms eased three months later, the Daily Mail reports.
