Kong Petchkaew, 58, posted the video on social media on Friday. It shows his 89-year-old mother-in-law lying on her bed at home and crying out with pain.
Kong said that he was afraid that her condition would worsen if she does not get medical treatment quickly.
Bangkok and surrounding provinces like Nonthaburi are facing a severe shortage of hospital beds as Covid-19 cases surge.
Kong revealed that his wife, 64, and nephew, 18, had also contracted the virus.
He added that he cannot leave the home, as he is a high-risk person.
This is not the first time Kong’s family has made headlines.
Earlier this week, his home was sealed from outside by his neighbours over fears the family could infect others in their community.
After the story was highlighted, wooden planks hammered over the home’s door were pulled out. Kong said he has filed a police complaint over the incident.