In his early 80s, my grandfather's gait slowed to a shuffle, he struggled to get in and out of cars and lived in fear of falling.

Also in this article: The Right to Know Your Responsibility as a Patient

"Parkinson's disease," his doctor pronounced. He wrote out a prescription, which my grandfather took diligently, never disclosing his condition to the family.

Three years later, his condition grew neither better nor worse, but he grew skeptical and sought a second opinion. The physician performed a CT scan, or, as my grandfather described it, "X-rayed my mind." That test found two spots on his brain pinpointing damage from small strokes that had skewed his sense of balance. The doctor took him off the medication and prescribed physical therapy instead.

The experience chipped a crack in my grandfather's faith in the all-knowing physician. Although he doesn't blame the first doctor for the misdiagnosis, he says he was disappointed at the mistake.

Today he still trusts his doctors to make sound decisions about his care, but he's quicker to question them. "I'd probably go to another doctor if I had a diagnosis that doesn't seem right," says my grandfather, now 88. "I don't think they would diagnose somebody wrong on purpose. But they make mistakes. You've got to be careful."

For seniors who grew up with a medical model that relied on the doctor's expertise and the patient's obedience, the health complications of aging may be a wakeup call to a new approach.

"A lot of older patients regard their health-care provider as very knowledgeable and almost intimidating," says Carolyn Duke, a geriatric clinical specialist and assistant professor of nursing at St. Louis University School of Nursing. "They just need to be encouraged that they have the right to know and they deserve to know [about their own health care.]"

One key, she says, is to see yourself as a client, entitled to the services for which you are paying. Imagine how you would handle similar questions or concerns about your personal finances or investments, Duke suggests.

"You have a pretty good knowledge of your interest rates, so you should have a good knowledge of your condition and medication," she says. "You feel comfortable talking to your banker; you should feel comfortable talking to your physician."

If you feel it would be disrespectful talking to your doctor regarding doubts about your treatment or diagnosis, try to view the exchange as a dialogue instead.

"Don't be afraid to ask if there are any alternatives to consider in [your] treatment," says Dr. Arlene Curry, an emergency room attending physician at St. Vincent Catholic Medical Centers of New York. "It doesn't really challenge the relationship a lot, but at least it's an empowerment of choice."

As a consumer, Duke says, you should expect your medical needs to be taken seriously. "Not always met, but addressed,-- she says. If the doctor doesn't respond to your questions or concerns, ask yourself if he or she is the right doctor for you, Duke says. If not, consider seeking a new physician or a second opinion.

If you're on Medicare, or on a health plan with limited prescription coverage, you'll want to keep an eye on costs. And since many seniors take multiple medications, keeping your prescriptions to a minimum may help reduce the risk of side effects or drug interactions.

"The risk of overmedication - is a major problem with the elderly," says Dr. Anand Kumar, an associate professor of geriatric psychiatry at the University of California, Los Angeles.

Ask your doctor about your medications' costs, effectiveness and side effects. He or she may be able to prescribe inexpensive alternatives to costly drugs, or switch you to a medication with fewer troublesome side effects. Ask whether physical therapy or rehabilitation might allow you to cut back on, or even eliminate, some drugs.

Don't worry that your doctor will be offended by your concerns. He or she will probably welcome your input, Curry says. "We tell [patients] - that if a treatment isn't working to report that to the doctor, who may not know."

Advance planning for doctor visits can compensate for any memory problems you may experience. Write out a list of questions before each visit. Bring a family member along for backup. Your son, daughter, spouse or sibling may offer important observations about your health, and can help remind you of crucial questions or concerns during the office visit.

Remember that you're responsible for carrying out your doctor's instructions at home. Don't leave the office before you understand them.

"If the physician is talking in medical terms, which most physicians do, [seniors] instead of just sitting and nodding their head and saying OK, [they] need to be able to say to the health-care provider, "I don't understand this," Duke says.

Your doctor's ability to help you is only as good as the information you provide. Make sure you let him or her know all the medications and food supplements you're taking, and any changes in your condition. New symptoms -- like memory loss or incontinence -- may be worrisome or embarrassing, but your doctor can't help you unless you disclose them.

"We try to be as open as we can, because hiding information won't be helpful to anybody. In fact it may be harmful," Curry says.