Actor Dennis Quaid has revealed he is thankful for the "happy ending" to his twins' overdose ordeal.

Quaid's twins, Thomas Boone and Zoe Grace, were born last November but later given an accidental overdose of blood thinner Heparin after being admitted to Cedars-Sinai Medical Center in Los Angeles.

"It's the greatest thing to hold those kids and see their faces because we had a happy ending," Quaid told People.

"It's great to be a normal dad with the normal problems of not having enough hands for both of them."

The Vantage Point star admitted the overdose incident changed the way he looked at life.

"I do have a greater appreciation of life in general. If they hadn't made it, it really would have changed my life. But they did survive. So it changed my attitude."

The 53-year-old said that Zoe and Boone are in a "fantastic" condition. "Their progress and their development appears to be completely normal - aside from being a Quaid," joked the actor.

Quaid and wife Kimberley, 36, have filed a lawsuit against drugs company Baxter Healthcare, who manufacture Heparin, accusing it of negligent packaging, which caused hospital workers to mistake adult vials for children's.