What time of day should I take my medicine?

What time of day should I take my medicine?
Credit: AI-generated image (disclaimer)

Whether you need to take a drug at a specific time of day depends on the medication and the condition you are treating. For some medicines, it doesn't matter what time you take it. And for others, the pharmacist may recommend you take it at the same time each day.

But we estimate that for around 30% of all medicines, the time of day you take it does matter. And a recent study shows blood pressure medications are more effective if you take them at night.

So, how do you know if the timing of your medication is critical?

When timing doesn't matter

In most cases, it's not important when you take your medicine. For instance, you can take non-drowsy antihistamines for hay fever, or analgesics for pain when you need them. It doesn't matter if it is morning, noon or night.

What is more important is the time interval between each dose. For instance, paracetamol needs to be taken at least four hours apart, any closer and you run the risk of taking a toxic dose.

Even when a medication doesn't need to be taken at a particular time, the pharmacist may still recommend you take it at the same time every day anyway.

This daily pattern helps remind you to take it. An example is taking the oral contraceptive at the same time each day, simply out of habit.

For the mini pill, taking it at the same time is actually necessary. But the actual time of day can be whatever works best for you.

When does it matter?

It may seem fairly obvious to take some medicines at particular times. For example, it makes sense to taking sleeping medications, such as temazepam, at night before you go to bed.

Some antidepressants, such as amitryptyline or mirtazapine, have drowsy side effects. So it also makes sense to take them at night.

For other medicines, taking them in the morning is more logical. This is true for diuretics, such as furosemide, which helps you get rid of excess fluid via your urine; you don't want to be getting up in the night for this.

What time of day should I take my medicine?
When a medicine needs to be taken at a specific time, this will be indicated on the box. Author provided

For other medications, it's not obvious why they have to be taken at a particular time of day. To understand why, we have to understand our circadian rhythm, our own internal body clock. Some systems in our body work at different times of day within that rhythm.

For instance, the enzymes controlling cholesterol production in your liver are most active at night. So there may be some benefit to taking lipid (cholesterol) lowering drugs, such as simvastatin, at night.

Finally, sometimes it's important to take medications only on particular days. Methotrexate is a used for rheumatoid arthritis and severe psoriasis, and the timing of this medication is critical.

You should only take it on the same day once a week, and when taken this way it is quite safe. But if you mistakenly take it daily, as happened recently with a patient in Victoria, then it can cause serious illness or even death.

What about blood pressure medicines?

One of the ways the body regulates blood pressure is through a pathway of hormones known as the renin, angiotensin and aldosterone system.

This system responds to various signals, like or stressful events, and controls blood volume and the constriction of blood vessels to regulate your blood pressure.

Importantly, this system is more active while you're asleep at night. And a recent study, which found blood pressure is more effective at night, may change the way we use medicines to treat .

Two types of drugs typically prescribed to are angiotensin converting enzyme (ACE) inhibitors, such as perindopril, and angiotensin receptor blockers (known as ARBs), such as irbesartan. These drugs dilate blood vessels (make them wider) to reduce your blood pressure.

Until now, doctors and pharmacists have often advised patients to take these medications in the morning, assuming it's good to have a hit of the drugs when you're up and about.

But this study found taking at night produced a significant reduction (45%) in , including fewer strokes, heart attacks and heart failure compared to taking them in the morning.

Taking them at night also meant people's pressure was better controlled and their kidneys were healthier.

So if you take one of these drugs to control your and aren't sure what you should do, talk to your pharmacist or doctor. While evidence is building to support taking them at night, this might not be appropriate for you.

Provided by The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.The Conversation

Citation: What time of day should I take my medicine? (2019, November 1) retrieved 24 June 2024 from https://medicalxpress.com/news/2019-11-day-medicine.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

Blood pressure drugs help keep heart trouble at bay, FDA says

2 shares

Feedback to editors