As an expectant mom, Kendra of Brooklyn, New York wanted the best for herself and her baby. Part of that care was a prenatal vitamin.

My doctor gave me a prescription for the prenatal vitamin, Primacare One, wrote Kendra. I dropped off my prescription at the CVS pharmacy and when I returned to pick up the prescription, I was instead given Prednisone.

The problem Kendra encountered is one of the most common prescription errors -- the kind that occurs when a pharmacist cant read the prescription properly. Instead of contacting the authorizing physician to confirm the prescription, the pharmacist plays Russian roulette with someone elses life.

Kimberly, of Hudsonville, Michigan, ran into a similar problem at Walgreens.

Kim wrote that the pharmacist couldnt read the prescription and assumed it said Corgard, a blood pressure drug. However, Kimberlys husband didnt need a blood pressure drug. He needed Cortef, a drug to treat his brain tumor.

Walgreens was also the target of another complaint, this time from Elana, who lives in Cranston, Rhode Island.

Elana said that her five-year-old daughter spent a very uncomfortable and scary five hours in the emergency room due to lethargy and vomiting. The Walgreens pharmacist gave the correct medicine, but it was 10 times the prescribed dosage, complained Elana.

Light rings

How would you like to use an eye drop to help your vision and instead end up seeing rings around street lights? A Mount Laurel, New Jersey man knows exactly how it feels.

I talked with Earl, who visited his CVS pharmacy for a prescription eye medication. He carefully read the box which said to put a drop in the left eye every six hours.

No problem, Earl thought. But it was a problem, because when Earl later read the paper instructions, he saw that the medication was for ear use only.

I called CVS and found that they gave me the wrong medicine. Now I have only one good eye, and CVS didnt even say they were sorry, said Earl.

No apologies

Not hearing Im sorry after a pharmacy mistake is typical, according to one California-based pharmacist who spoke on the condition of anonymity.

We are told to never apologize for giving a wrong prescription because it automatically implies guilt. I suppose the company wants to leave that to the attorneys, the pharmacist said.

Unfortunately, pharmacy errors happen more frequently than you might think. The Institute of Medicine took a hard look at prescription errors, including those in hospitals and long-term care facilities. The study, released in July 2006, showed that at a minimum, 1.5 million consumers annually are killed, injured, or made sick by drug errors.

Then there are the errors that are never caught or reported, not to mention the debate as to what constitutes an error.

How they happen

ConsumerAffairs.com contacted pharmacists across the country in an attempt to learn how mistakes happen -- and what you can do to make sure it doesnt happen to you. Not surprisingly, many of those we contacted did not want their name or city published.

So how do mistakes happen?

There were common themes among pharmacists we interviewed. The first:

Unreadable prescriptions I dont know how some doctors ever passed med school with their lousy handwriting, commented one New Jersey pharmacist. I have to call the doctor to verify the script, then I cant reach the doc, and the whole time the customer is waiting for their medicine.

If I see one big problem, its with the doctors writing, said Dan Freund, owner of a Medicap pharmacy in Farmington, Missouri. If Im wrong about one little letter, it could change the name of the drug. Its even worse if its a first-time customer. And Im trying to read this chicken-scratch while working in a busy environment.

That busy environment leads to the second biggest issue for pharmacy employees:

Never-ending distractions Its nothing to have someone on the phone, someone at the drive-thru, all while youre trying to fill a prescription. And then someone walks in and starts asking questions, said Susan Freund, Dans pharmacist wife and partner at the Missouri pharmacy.

In pharmacy training, it is drilled into each student that before the prescription is given to the customer, that script needs to be checked three times for accuracy, Susan said. But, unlike a surgeon who is working in a relatively quiet atmosphere, were sometimes trying to verify things in the middle of a phone-ringing circus.

Working in a hectic pharmacy might come with the territory, but when it comes to reading a doctors handwriting, one possible solution might be to get rid of the paper prescription.

Some physicians are now moving to a paperless prescription process. One example is Dr. Raul Borrego, a Missouri internist.

Moving to paperless has slowed me down, but I have no doubt that the chance of a prescription error will lessen, noted Raul. Instead of just jotting down the drug and instructions, I have to input everything into a laptop computer.

Its a very precise system. Once I choose and verify the drug, I then must choose the dosage, frequency, etc. The pharmacy will receive it in text, so they dont have to read my writing. Even my wife says I have terrible handwriting, Borrego said.

"Dont trust us"

It might sound odd for pharmacists to say we shouldn't trust them, but that's what several told us.

I wish more people would ask questions, said one Illinois pharmacy tech. I consider myself good at what I do, but I know I have made a mistake in the past, she said. Customers have to realize we are as human as they are.

What you can do

There are measures you can take to help ensure your prescription isn't among the hundreds of thousands that go awry each year. They include:

Dont be naive. Stay up to date on your condition and medication. Ask your doctor the name of the drug and why it is being prescribed. Once at the pharmacy, ask them the same thing. One simple question from you could alert the pharmacy to a possible error.

Diagnosis If your doctor writes the prescription on paper, ask him or her to write why the drug is prescribed. For instance: "Toprol 100 Milligrams ... for blood pressure." Additionally, make sure you can read the prescription because if you cant, maybe the pharmacy cant either.

• Get a copy. If the physician sends the prescription electronically, ask for a copy.

Get the name. If the prescription is called in, ask the doctor the exact name of the drug. Example: Your doctor says he is calling in an antibiotic ... you ask for the specific name of the antibiotic. Make a note of it and compare it to what the pharmacist gives you.

Verify. Verify the name on the bottle and packaging. Many mistakes arise when the pharmacy gives the wrong prescription based on someone having the same last name.

Go off-peak. Are you filling the prescription at the beginning of the month? According to research, there is an increased chance of error at busy times.

Go online. Use the internet to your advantage. Before taking any medication, verify what the drug is, based on color, shape, or the imprint code. Two good resources are the Pill Identification Wizard from drugs.com, and the RxList Pill Identification Tool.

Mistakes do happen

So what happens when the pharmacy makes a mistake and you know it? ConsumerAffairs.com receives many complaints about drug errors and questions about how to handle the situation.

Suvithia, of Frisco, Texas, wrote that after she received the wrong prescription, the insurance company for Walgreens offered an apology compensation in the hopes of keeping the case out of court.

The insurance company offered $350.00, Suvithia said. My husband and I declined their offer and then we received a letter offering a $1,000.00 settlement.

So what should you do when mistakes happen to you? The answer depends on whether you have been seriously harmed or merely inconvenienced.

Serious harm

If you or a family member suffer grievous harm from an incorrect prescription, or if someone dies because of a pharmacy error, do not contact the pharmacy. You should never try to negotiate a settlement yourself and, just as your insurer tells you not to make any statements after a serious traffic accident, you should not communicate with the pharmacy in any way. You can only hurt your case.

Instead, collect all the evidence -- any remaining medication, hospital and doctor bills, receipts, death certificates, etc. -- and lock them up in a safe place, preferably a safe deposit box.

Also, take notes. Write down what happened and when, get the names of doctors, nurses, pharmacists and everyone else who played a role in the accident. Do it now, while your memory is fresh. Put the notes in the safe deposit box with the rest of the evidence.

Once you have secured all of the evidence, you must find the most accomplished and most experienced personal injury lawyer in your area. Forget everything you have heard about what a litigious society we are and how too many people are filing lawsuits.

The fact is that more than 90% of lawsuits are filed by businesses. It's not lawsuits filed by greviously injured consumers that are clogging the courts. If you have been harmed, the legal system is the place to go for justice. That's why it's there.

You must find the right lawyer. Most lawyers, like most of anything else, are just so-so and most never go to trial and do not aggressively represent personal injury cases. You need to find an accomplished lawyer in your state who: a.) only represents injured consumers and b.) whose practice consists largely of trial work.

Remember that most lawyers represent corporations. You want to find the local Johnnie Cochran, the attorney who defends the little guys -- because all of us are very little guys indeed when we are up against a major corporation.

Otherwise ...

If you are not seriously harmed or killed, there is no reason to hire a lawyer. There is also no reason to expect the pharmacy to do much of anything about the error. Pharmacies won't admit fault, even when no serious injury occurred.

If you believe the pharmacist should be held accountable for being negligent and putting your well-being at risk, you should file a complaint with your state pharmacy board, the entity that licenses pharmacists.

Each state's board has an established complaint procedure. You can find a list of the state boards at the National Association of Boards of Pharmacy Web site.