Report: Massive OD of Benadryl killed Coeur d’Alene man

Larry Isenberg didn’t drown.

The 68-year-old whose body was found in Lake Coeur d’Alene last spring after an outing with his wife, Lori, died from a drug overdose, according to a coroner’s report.

The one-page report obtained from the Kootenai County Coroner’s Office states that Isenberg’s cause of death was diphenhydramine toxicity, which means he died from an overdose of Benadryl.

Benadryl is a brand name for diphenhydramine, an antihistamine used to treat allergies. Because it causes drowsiness, it is also used as a sleep aid.

Normal dosages are between 100 and 1,000 nanograms. The level reported in Isenberg was a lethal 7,100 nanograms, according to a search warrant issued in Spokane County.

Isenberg was last seen by his wife, Laurcene “Lori” Isenberg, 64, on a boat outing Feb. 13 on Lake Coeur d’Alene the day the Coeur d’Alene Press reported that she was under investigation for embezzling money from a local nonprofit. She was later charged with stealing more than a half million dollars. Isenberg told authorities her husband fell from the couple’s boat into the lake at Powderhorn Bay north of Harrison.

As Coeur d’Alene police opened an investigation into the embezzlement, sheriff’s deputies continued to search for Larry’s body, and Lori was released from jail on a $75,000 bond.

She failed to appear at subsequent court hearings and is wanted on a $500,000 bench warrant issued in June after she did not show up for her arraignment. She was last seen by authorities months earlier.

The cause of death report spurred investigators this month to serve search warrants for evidence of conspiracy to commit murder and first degree theft at the Spokane homes of Lori Isenberg’s children.

A warrant filed Thursday in Superior Court in Spokane, where Lori Isenberg’s daughters live, reiterates the Idaho coroner’s report.

The warrant indicates Isenberg’s daughters, Jessica Barnes and Amber Hosking, are under investigation for conspiracy to commit first degree murder and first degree theft.

According to the warrant that jointly used information from investigators in Spokane County and the Kootenai County Sheriff’s Office, Larry and Lori Isenberg may have had marital difficulties prior to Larry’s death.

Neighbors interviewed by investigators reported that the normally inseparable couple’s daily walks ended months before Larry’s death.

One neighbor noted, “Over the last six months, they never saw them together,” according to the warrant.

Investigators also noted handwritten changes made to the will of Larry Isenberg. The estate would be divided so Lori’s children would get the larger share, or, “80 percent to Lori’s kids and 20 percent to Larry’s kids,” according to the warrant.

One of Larry Isenberg’s friends also became suspicious after receiving a text message from Larry the morning he reportedly drowned. The message contradicted what the two men had spoken about a few days earlier and ended with an emoji.

“Larry never uses emojis,” the friend told authorities.

The observation was confirmed by investigators who scoured Larry’s and Lori’s phones as part of subsequent investigations.

“Larry never used emojis in contrast to Lori’s regular use of emojis,” an investigator wrote.

In the morning of Feb. 13, the Isenbergs’ boat was apparently launched at Sunup Bay on the west side of Lake Coeur d’Alene, about 4 miles from where Lori Isenberg called to report her husband had gone overboard.

She told authorities she waited two hours to report the incident because she had left her cellphone in Larry’s pickup truck and she was unable to find Larry’s cellphone, thinking he had it when he fell into the water while fixing an electric motor on the boat’s bow.

She later found his phone in a blanket. She told another investigator it was found in the boat’s driver’s side dash.

Blood drops were found on the electric motor’s foot control on the front of the boat and in several other places toward the front.

Lori told deputies she bloodied her nose in an attempt to pull Larry from the water.

Samples were taken and the results are pending, according to the report.

The body of Larry Isenberg, wearing camouflage pants and a black sweatshirt, was found around 1 p.m. March 1, on the west side of the lake along the northern shore of Windy Bay.

In autopsy findings, Spokane County examiners reported the results of a gastric content toxicology report showing unmetabolized amounts of diphenhydramine at 19,000 nanograms per liter. Additional findings show “the presence of THC (marijuana) was present at levels consistent with normal usage.”

Dr. Sally Aiken of the Spokane County Medical Examiner’s Office advised investigators “there were no visible signs of a stroke and no evidence of drowning,” according to the report.

A search for Lori Isenberg that includes bounty hunters continues.

This story originally appeared in The Coeur d’Alene Press. Click here to subscribe to the newspaper and stay up to date on news happening in northern Idaho.