High on over-the-counter medication, two hikers from Westmoreland County slipped and fell to their deaths in Forbes State Forest Park, state police said Thursday.

Tests show that Sara Baum had ingested four times the normal dose of chlorpheniramine before she lost her footing in the park near Jennerstown on March 29, police said.

"The toxicology reports indicate that they were under the influence of a drug," said Trooper Scott Mackanick of the Pennsylvania State Police. "It's an antihistamine-type drug found in cough medicine."

Chris Cardy, who had ingested 30 times the normal amount, climbed down to try to reach Baum -- who had already been killed in a 16-foot fall -- but instead fell 39 feet to his death, police said.

A group of hikers found the gearless bodies of the Greensburg woman and the Ligonier man 30 feet below a point known as Beam's Rock, police said.

Baum, 24, a mother of one, fractured her skull, and Cardy, 25, died of a broken neck, police said.

No other drugs were in their systems, according to the test results.

Both deaths have been ruled accidental. Police said they have no reason to suspect anybody else was involved.

Witnesses who saw the couple before they were found dead said there was no sign of an argument. And police said they found no evidence of a struggle. Friends said the couple was close and never argued.

"So, at this point, we are ruling it two accidental deaths based on the all the evidence and things that we had found," said Cpl. Ed Thomas of the PSP.