A Bible-studying South Carolina woman who once griped online that her hubby was unfaithful was charged with murder — after admitting to poisoning him with eye drops, officials said.

Lana Clayton, 52, was booked Friday after an autopsy uncovered a high amount of tetrahydrozoline in her husband’s body, officials said.

The chemical is found in over-the-counter drops, such as Visine, and reduces redness by restricting blood vessels. But when it’s swallowed, it acts as a neurotoxin and attacks the nervous system.

Lana Clayton admitted to spiking her husband’s water with eye drops over a three day span, between July 19 and 21, the York County Sherriff’s office said.

Steven Clayton, 64, was found dead July 21 in their palatial home, worth over $800,000, in Clover, South Carolina, about 30 miles southwest of Charlotte, N.C. It appeared he had fallen down the stairs.

The home was designed as a copy of George Washington’s Mount Vernon estate, and Steven Clayton had carefully worked to restore his property, according to The Herald of Rock Hill, S.C.

An accountant, Steven Clayton was the founder of Physical Therapy Resources, a national company with branches throughout the United States. He retired in 1995, according to his obituary in the Herald.

His funeral was held in the home’s back yard on Aug. 4, before the autopsy results revealed the cause of death, according to WSOC-TV in Charlotte.

One neighbor said she knew Lana Clayton from a neighborhood Bible Study group.

A friend told a local newspaper that Lana worked in nursing for the VA hospital in Charlotte. Police have not released a motive for the crime.

She posted a comment on what appears to be her little-used Facebook page in March 2010 that suggested her husband was unfaithful. “My husband is not a drunk he had an affair. However, he is the father of my children and my kids look at my Facebook. Soooo. I do appreciate the support though.”

She had already started legal action concerning the estate, which also included a lot next door to the home worth nearly $400,000, the Herald reported.

Neighbor Ken Sanford told the Rock Hill, S.C., Herald that “seemed like a sweet lady,” and “Steven was very proud of her accomplishments.”

“I am just stunned,” Sanford said.

Lana Clayton was also charged with unlawful malicious tampering of food. Because she is charged with murder, she will not be released on bond. It’s unclear if she has yet named a lawyer.

An Oklahoma native according to her Facebook page, she has no prior criminal record in South Carolina, the Herald reported.

With Post Wires