MADISON, Wis. -- Pharmacist Roberta Carrier said that she sees it happening a lot lately. As more generic drugs are approved by the Food and Drug Administration for over-the-counter sales, prescription drug coverage from health insurance plans disappear.

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"I can be quite a surprise for people," Carrier said. "Two weeks later, you're in there for something else and all of a sudden you're not covered anymore."

The trend is affecting some of the most popular drugs -- Claritin, Prilosec, Zyrtec and Zaditor, the eye drop, WISC-TV reported.

Carrier said that she tries to work with physicians to help patients avoid high costs.

"What usually happens in those cases is that we end up talking to their doctors to get them switched to something that's still prescription, generic or not, but still prescription, so they can get the coverage," she said.

Most of the patients caught without coverage have national plans, like Medicare Part D, which doesn't cover any version of Claritin or Zyrtec.

For many in the area, there's hope, Carrier said.

"We are very fortunate in Madison to have some very progressive local insurance companies that have realized that physicians are going to prescribe what's covered by prescription drug companies," she said.

Officials with Group Health Cooperative said that in certain instances, they've judged drugs to be a better value to some of the prescription alternatives that were still available, and so decided to make an exception in their coverage.

What if a patients' plan doesn't make the exception?

For some, generics drugs are the way to go. In some instances, patients can't tell the difference between Loratadine and its brand name Claritin. But after awhile, the cost for the brand-name version will pile up, WISC-TV reported.

Carrier said that she urges patients to talk to their pharmacist to come up with a cheaper solution.

"We try to work with them to find something that is covered by the insurance but with the local, a lot of them are covering the over the counter because it is dramatically less than the brand used to be," she said.

Locally, many plans, including Group Health Cooperative and Physician's Plus, make exception for these particular drugs.

Officials said that if patients aren't covered on their prescription drug plan and they need help paying for medicines, there are state agencies that can help.