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Prevent Medical Errors


Medical errors are mistakes in health care that could have been prevented. They can occur in hospitals, clinics, surgery centres, doctors' offices, nursing homes, pharmacies, and your home. Errors can involve medicines, surgery, diagnosis, home treatment, equipment, or lab reports. They are often caused by a lack of good communication. Medical errors may result in injury or death.

Some examples of medical errors are:

  • Having surgery done on the wrong area of the body.
  • Getting the wrong meal while in the hospital, such as a regular meal when you need a salt-free meal.
  • Getting the wrong medicine or the wrong dose of medicine.
  • Getting a diagnosis or lab test that is not correct.
  • Having a piece of medical equipment fail or not work the right way.

What You Can Do to Prevent Medical Errors

The best thing you can do to prevent medical errors is to be involved in your health care. Learn and know about your health problem, medicine, and treatment as best you can and take part in making all decisions about your care. Talk to everyone who is involved in your health care. This includes your doctors, other health professionals, family, and friends.

The following steps can help you prevent medical errors.

  • Speak up if you have questions or concerns.

    You have a right to question anyone who is involved with your care. This is easier if you have a doctor you feel comfortable with.

  • Make sure that someone is in charge of your care.

    This is especially important if you have many health problems or are in a hospital. For example, this could be a doctor that helps to coordinate all the team members providing care for you.

  • Make sure that all health professionals involved in your care have health information about you.

    Don't assume that everyone knows everything they need to know.

  • Ask a family member or friend to be there for you.

    Take someone along with you to a doctor's visit or to the hospital. Make sure this person will speak up for you and get things done if you're not able to help yourself. Even if you don't need help now, you might need it later. Make sure this person knows your wishes for your care.

  • Know that "more" is not always "better."

    Find out why a test or treatment is needed and how it can help you. You might be better off without it.

  • If you have a test, don't assume that no news is good news.

    Ask when and how you will get the results of tests or procedures. If you don't get them when you expect to, don't assume that the results are fine. Call your doctor and ask for the results and what they mean for your health and treatment.

  • Learn about your condition and treatment.

    Ask your doctors if your treatment is based on the latest evidence. You can get information about your condition and treatment from your local library, respected websites, and support groups.

Prevent Errors With Medicines

Medical errors are mistakes in health care that could have been prevented. If you take medicines, there are things you can do to help prevent these kinds of errors.

  • Tell your doctor and other health professionals about all the medicines you are taking.

    This includes prescription and over-the-counter medicines as well as natural health products such as supplements, vitamins, and herbs. You can give your doctor a master list of medicines. Or you can put all your medicines and natural health products in a bag and take them with you when you see your doctor.

  • Tell your doctor about any drug allergies or other reactions to medicine you have.

    If you have an adverse reaction to some medicines, your doctor can help you find another one or change the dose. This can help you avoid getting a medicine that might harm you.

  • Stay in touch with your doctor if you are taking pain medicine.

    Your doctor needs to know how well your pain medicine is working. If your pain medicine is not working, don't take it more often or in a larger dose. Talk to your doctor first.

  • Tell your doctor about side effects that are severe or unexpected.

    Don't just try to live with the side effects. Your doctor may be able to change the medicine or change how much you take to help with side effects.

What to ask your doctor or pharmacist

Using medicines can be confusing, especially if you take a lot of medicines. You need to keep track of when and how to take them. And prescriptions and labels are not always easy to understand. So it's easy for an error with medicine to happen.

To help prevent errors, ask your doctor or pharmacist questions about each of your medicines.

What do you mean?

If you don't know why you're taking a medicine or how to take it, ask. Not knowing how to follow instructions can cause errors with medicine.

How do I take this?

Make sure you know how your doctor wants you to take your medicine. Write down how much medicine you need to take, and how many times a day you take it.

How long do I take this?

Find out if you need to finish the bottle of medicine or if you can stop taking the medicine when you feel better. Ask if you need to get a refill or if you can stop treatment when the bottle is empty.

Is it safe to take this medicine with other medicines?

Taking certain medicines together may cause a bad reaction. This is called an interaction. To make sure that you don't have a bad reaction from your medicines, tell your doctor or pharmacist what other medicines or natural health products you are taking. And make a list of any medicines that you shouldn't take.

Is there anything I shouldn't do?

Make sure you know about any foods, drinks, or activities you should avoid while you take the medicine. Find out what medicines may not be safe to give your child.

What do I do if I miss a dose?

With some medicines, you wait until the next time you take it. With others, you need to make up the dose. The information sheet that comes with your medicine may tell you what to do if you miss a dose.

What are the side effects?

Know what side effects you can expect and what to do if they occur.

Your pharmacist can also help with questions such as:

Is this what my doctor prescribed?

When you get your medicine, check to make sure it's the right medicine. Read the label to make sure you have the correct medicine, at the correct dose. If you are refilling a prescription and the size, shape, or colour of the pills looks different than before, ask the pharmacist about it.

How do I measure the medicine if it's a liquid?

Liquids can be hard to measure. The teaspoon you use for cooking, for example, may hold a different amount from what the doctor means. It may also be hard to know which line to fill a syringe or dropper to.

What does the label say?

Medicine labels can be confusing. For example, ask if "take 1 time a day in the morning" means you can take it any time in the morning or early in the morning. If you have any questions about what a label says, ask about it. Do this for both prescription and over-the-counter medicines.

Keeping track of your medicines

Using medicines can be confusing, especially if you take a lot of medicines. Here are some tips to help you keep track of when and how to take them.

  • Plan a daily schedule of medicines.

    Put your schedule somewhere where you will always see it and where it's easy to find.

  • Keep your pills in a pillbox.

    Get a pillbox that holds a week's worth of pills.

  • Set reminders.

    Use your cell phone, a watch you can program, a scheduling program on the computer, or other types of timers to remind you when it's time to take your medicines.

  • Learn more about how to take medicines safely.

    Visit for more information.

Learn more


Prevent Errors in the Hospital

Many medical errors happen in the hospital. For example, you may receive the wrong meal or medicine. Here are some questions you can ask to help avoid errors:

Have you washed your hands?

It may sound like an odd thing to ask hospital workers, but doing so can help prevent infections.

Am I the right person?

Make sure hospital workers check your wristband or ask your name before you accept something. You want your own food, medicine, treatment, and bill—not someone else's.

How long do I need this? Is it safe?

Ask about each step of your care. For example, if you have a urinary catheter, ask about it. The longer you have a catheter, the more likely it is you'll get an infection.

What do I do when I go home?

Before you leave the hospital, ask your doctor to explain and write down your treatment plan. Ask about your medicines, what you can or can't do, and when you can return to work, school, or other activities. If you're given an instruction sheet, read it and be sure you know what it means.

Before going to a hospital for a surgery or procedure, ask how often the procedure is done. Research shows that you likely will have better results when you go to a hospital that has a lot of experience with a health problem or surgery.footnote 1

Learn more

Prevent Errors During Surgery

Before you have surgery, be sure that you and all your doctors know what is going to happen. Ask about:

Your surgeon's experience.

You may get better results if your surgeon has done a lot of operations.

When you'll have your surgery.

Your surgical team may be more alert in the morning.

How to prepare for the surgery.

Ask your doctor if you have to stop taking any medicines or stop eating or drinking before the surgery. Ask your surgeon to mark your skin in advance to point to the correct area for surgery. It's rare that surgery is done on the wrong part of the body, but it can happen.

What to do after surgery.

Ask about medicines you may need after surgery and what you need to do at home. Ask about what you can or can't eat and how to take care of surgical cuts (incisions). Ask when you need to call for help.

Be sure to tell your doctors:

  • Whether you have ever had a bad reaction to anesthesia. Anesthesia is the medicine you get before your surgery to make you sleep or feel relaxed and help with pain.
  • Whether you take any natural health products.
  • Whether you have an advance care plan. If you don't have one, you may want to prepare one so your doctor knows your health care wishes.
  • If you get a cold, fever, flu, or other illness close to your surgery date.



  1. Agency for Healthcare Research and Quality (2011). 20 Tips to Help Prevent Medical Errors. Patient Fact Sheet (AHRQ Publication No. 11-0089). Rockville, MD: Agency for Healthcare Research and Quality. Also available online:


Adaptation Date: 2/17/2023

Adapted By: Alberta Health Services

Adaptation Reviewed By: Alberta Health Services

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