Informed Consent: Your Right to Ask Questions About Any Treatment

Have you ever walked out of an appointment and only then thought of the question you meant to ask? You are not alone. Appointments are short, the language can be technical, and it is easy to nod along. But here is something many people never hear: understanding a treatment before you agree to it is not a favour your doctor grants you. In the UK, the US, Canada and across the EU, it is a recognised right.

What Does Informed Consent Actually Mean?

Informed consent is the principle that you should understand what a treatment involves, what it might do for you, what the risks are and what your other options are, before you decide whether to go ahead. It applies to medicines, procedures, tests and screening alike.

It is not just a form you sign. A signature records a decision. Informed consent is the conversation that leads up to it, and the understanding you carry out of the room.

Importantly, informed consent is not about saying no. Plenty of people hear all the facts and choose the treatment their doctor recommends, with far more confidence than before. The point is that the choice is genuinely yours, made with the information you need.

Your Rights in the UK, US, Canada and EU

In the UK, a 2015 Supreme Court ruling, Montgomery v Lanarkshire Health Board, changed the standard. Doctors must take reasonable care to make sure you are aware of any material risks and of reasonable alternatives. A risk counts as material if a reasonable person in your position would consider it significant, or if your doctor knows, or should know, that it would matter to you personally. In other words, the test is built around the patient, not only around what other doctors would typically say.

Canada reached a similar position decades earlier. In Reibl v Hughes (1980), the Supreme Court of Canada held that doctors must disclose the material risks a reasonable person in the patient's position would want to know.

In the US, the landmark case Canterbury v Spence (1972) set out a patient-centred standard, although the exact rules still vary from state to state. Some states judge disclosure by what a reasonable patient would want to know, others by what a reasonable doctor would usually disclose.

Across the EU, the Charter of Fundamental Rights names the free and informed consent of the person concerned as part of the right to integrity of the person in medicine and biology.

The details differ, but the direction is the same everywhere: you are entitled to understand your options. (This is general information, not legal advice.)

The Simple Questions That Make a Real Difference

You do not need medical training to have a better conversation. A few well-chosen questions go a long way.

One widely used approach in the UK is BRAN, promoted by Choosing Wisely UK. It stands for: What are the Benefits? What are the Risks? What are the Alternatives? And what happens if I do Nothing, or wait a little longer?

Researchers in Australia tested an even shorter set of three questions: What are my options? What are the possible benefits and harms of those options? And how likely are each of those benefits and harms to happen to me? When patients asked them, doctors gave noticeably more information about options and about risks and benefits.

A few other questions are worth keeping in your back pocket. How strong is the evidence for this? How will we know if it is working? Are there side effects I should watch for? Is this something I can take time to think about?

The same questions are just as useful when the decision is about support rather than a procedure. If you or someone close to you is living with a serious illness, you can ask whether palliative care could help alongside your current treatment. Our article What Is Palliative Care? Why It's Not Just for the End of Life explains what that involves.

A practical tip: write your questions down before the appointment, and bring someone with you if you can. A second pair of ears helps, especially when the news is unexpected.

Shared Decision Making: You and Your Clinician on the Same Side

Health researchers have a name for this kind of conversation: shared decision making. Your clinician brings medical knowledge and experience. You bring something just as important, which is knowledge of your own life, your priorities and what matters most to you.

A good decision combines both. Two people with the same diagnosis can reasonably choose different paths because they value different things, such as recovery time, side effects, cost or convenience.

There is good evidence that tools which support this process help. A large Cochrane review of decision aids, such as leaflets and online tools that lay out options side by side, found that people who used them felt better informed, had a clearer sense of what mattered to them, and had more accurate expectations of benefits and harms.

One word of caution. Asking questions is always a good idea. Stopping or changing a prescribed treatment on your own is a different matter. If you have doubts about something you are already taking, raise it with your prescriber first so you can decide together.

Your health decisions belong to you. The best ones are made in partnership, with a clinician who explains and a patient who feels free to ask. So next time you are offered a test, a medicine or a procedure, take a breath and ask: what are my options, what are the benefits and risks, and what happens if I wait? You are not being difficult. You are doing exactly what good care is designed for.

This article is intended for informational and educational purposes only and is not medical or legal advice. Laws and guidance on consent differ between countries and change over time. If you have questions about a treatment, ask your doctor or pharmacist, and do not stop or change a prescribed treatment without speaking to your prescriber first.