A medicinal cannabis campaigner who walked from Cork to Dublin to raise awareness has taken her daughter abroad for treatment.

Vera Twomey's seven-year-old daughter Ava suffers from a severe form of epilepsy called Dravet Syndrome, which can be treated with medicinal cannabis oil.

She has now begun fundraising to pay for the trip and has so far raised more than €21,000.

She told Newstalk Breakfast her daughter's seizures have reduced by as much as 90%.

"We have set up a GoFundMe page to cover our costs for travelling to Holland to get treatment for our daughter.

"We're very, very sad that we've had to leave the country. We tried so hard, all we wanted to do was to stay at home."

Vera explains how the CBD oil works: "There are receptors in all our bodies to receive CBD oil, and when the CBD is administered... it actually calms the body, it reduces inflammation in the brain.

"When we began the CBD oil in October of last year our daughter had 11 consecutive seizure-free days.

"Her seizure control has been magnificent really since... I'd say her seizures are down by about 80 to 90%."

Administering CBD oil in Ireland is completely legal, but the THC component of the medicine is not.

THC is the principal psychoactive constituent of cannabis.

Vera says they were looking for an exemption here, which they could not get it.

But she says if they can prove the treatment works, they could be granted a licence to administer it here.

"The reason that we have arrived in Holland because the Government, the HSE, the neurologists have demanded that we would go to another country to provide evidence that this treatment will work for our daughter".