Mr Griffiths started selling pens for charity in 1997 and has raised about $250,000 for the Otago SPCA, Heart Children Otago, the newborn intensive care unit at Dunedin Hospital, and the Otago Community Hospice.
He has been missing from his regular spot in Albion Pl since he had a stroke on October 1.
"It slowed me down a bit," he said.
Mr Griffiths was released from hospital last week, and while his health was improving, it would take a while to figure out how to help his charities in the future.
"I probably won't go back in the same capacity, but I will be involved in the street day appeals."
Knowing he would not be able to support his charities as he used to was "disappointing" but he had to "get himself well".
This year, he had been fundraising for the SPCA, and its staff and volunteers had taken over pen sales in his absence.
The public had missed his presence on the street and he had received stacks of cards and phone calls from wellwishers.
Otago Community Hospice marketing co-ordinator Lyn Chapman said Mr Griffiths had been a "significant influence" on the streets of Dunedin and the money he had raised for the hospice was "amazing".
"We will desperately miss his presence and the profile that he gives his charities."
