I found this:
48 HOURS (10 p.m., CBS) - Peter Van Sant looks at two cases, from North and South Carolina, that involve murder by Visine eye drops. In the first,
Lana Clayton told police she found her millionaire businessman husband Steven Clayton dead at the bottom of the staircase in their Lake Wylie home in July 2018. At first, investigators believed he died from a heart attack. But Steven’s nephew, a police officer in a nearby town, was suspicious and the family asked for an autopsy and toxicology test. The tests showed that the chemical tetrahydrozoline — an ingredient in Visine and other brands of eye drops — was found in his blood.
When given orally, tetrahydrozoline can put someone in a coma in 15 to 30 minutes and cause a heart attack, forensic toxicologists working on the case say. Then, two months later — and 12 miles down the road in Mount Holly, N.C. — a young woman named
Stacy Hunsucker was found dead in her home by her husband Jason, and tetrahydrozoline was found in her system. Investigators believe it was a copycat killing. “48 Hours” reports on developments in both cases.
https://www.newsobserver.com/entertainment/tv/warm-tv-blog/article249897843.html#:~:text=The tests showed that the,working on the case say.