Before you start

This is a short book and you can read it in two or three sittings. It's about one habit, and the habit has two shapes. The first is stopping a medicine because you feel better, or because you feel fine, or because you never felt anything and can't see what it's for. The second is the slow version, where the tablet that was every morning becomes most mornings, then when you think of it, then when you find the packet. Nobody decides to do either. They happen in the gap between a prescription and a life.

I'm going to argue three things. The first is that the habit makes sense from the inside. Feeling better is what treatment is for, so stopping when you feel better looks like the natural end of it. A tablet for something you can't feel is hard to believe in. A missed day that changes nothing looks like proof that the tablet does nothing. The second is that the feeling you're using as your test is the wrong instrument, and there's research on why. For some medicines you feel fine because you're taking them, and the feeling ends when the medicine does. For others you'd feel exactly the same with or without them, because the thing they treat has no symptoms until it does something serious. And for a short course, feeling better on day four says nothing about what the prescriber intended for day seven. The third is practical, and it's the whole method. Take it the way the prescription says, and if you want to change that, stop that, or you've been skipping it, the next step is a conversation with the person who prescribed it or a pharmacist, not a quiet decision on your own. Chapters 20 to 22 cover how.

This book never tells you to stop a medicine, to take less of one, or to take more. It never tells you your prescription was right, either. That's a question for the prescriber, and the book's point is that it should be asked there and not settled by the drawer.

Three cautions.

If you're taking a medicine for a mental health condition and you've been thinking about stopping it, the NHS says not to stop suddenly or without talking to your doctor first, because stopping can bring withdrawal symptoms and some of them look like the illness coming back. Chapter 10 is about this. If you or someone you know is in a mental health crisis, the NHS has urgent help and you don't need to finish the book first.

If you've been skipping a medicine for days or weeks and you're about to restart it after reading this, ring a pharmacist first. Some medicines are restarted differently after a gap, and a pharmacist can tell you in a minute whether yours is one.

If the reason you're not taking a medicine is that you can't afford it, can't get to the pharmacy, or can't manage the number of tablets, that isn't a habit and it isn't a fault. Chapter 23 says who can help.

The notes at the back give my sources and their limits. Where I'm giving my own reasoning and not a finding, I'll say so.