Pat Kerr has cancer and as his doctor attempted to make a home visit, he was told to "wait until the protests were over".
Mr Kerr's daughter Nicky said the GP did make it to their home, but said it has made her scared for the future.
"If the roads are blocked we are sitting ducks. We can't get him to a hospital," she said.
"That's a real fear. It's already a very stressful situation without worrying if we can get him to the hospital or to medical attention.
"To me, the most important thing is someone's health, rather than anything else that's going on."
I don't even know if it's anger, it's disbelief that a protest and a flag is put ahead of someone in need of medical urgency.
Trouble flared across Northern Ireland on Friday evening, with much of the disorder concentrated in Newtownabbey and Carrickfergus.
Police were pelted with 33 petrol bombs and other missiles during disorder in the Co Antrim towns. In Newtownabbey, a double decker bus, which had been hijacked earlier, was set on fire.
Five baton rounds were deployed and the water cannon was used. In Carrick, two people, including a 15-year-old boy, were arrested and they appeared in court on Saturday accused of riotous assembly.
The teenager has been released on bail, while 30-year-old Aaron Andrews, from Oakwood in the town, was remanded into custody.
East Antrim DUP MLA Sammy Wilson said the disorder was damaging the cause and the community.
"The question is, do any of these protests get the protestors and all of us who want to see the flag up any closer to our objective of restoring the Union flag at Belfast City Hall, and of course the answer is no," he said.
Mr Wilson added that demonstrators need to find more peaceful, effective means of putting across their concerns.
"The objective at the end of the day is to try and make sure that our British identity is not eroded and if there are more positive ways of doing that then that's what we want to talk to people about, and find a direction which we can show them."