Ever got a doctor’s prescription to take a tablet “morning-evening”? Did it leave you wondering if 5 pm is as good as 8 pm for the evening dose? You’re not alone.

People who take regular medicines – like statins, blood pressure medicine or insulin – often find themselves wondering about the right time gap between doses. And while it is always suggested to take your medicines as per your doctor’s prescription, oftentimes those very prescriptions become a bit confusing.

What exactly does it mean when your doctor tells you to take a medicine twice a day? Just how much time difference are you supposed to keep between a morning and evening dose? Well, experts say that there is indeed a “right” time to take medicines. Yes, you heard it right. There is a specific time when you should take your medicines for maximum effect. Let us have a look at those timings and whether you can still take a tablet if you miss this time window on some days.

Two types of medicines

According to the US Department of Health and Human Services, there are two kinds of medicines: Those that require a standard dosing time and those that don’t.

Scheduled medicines

Schedules medicines or those with a standard dosing time are taken in repeated cycles – daily, twice a day, thrice a day or per hour. The scheduling is important to ensure that these medicines are present in precise therapeutic amounts in the blood to be effective.

The scheduled timing for most medicines is almost universally accepted. Here’s a quick peek:

Schedule Timing
Once daily medicines 9 am (8 am for children)
Twice a day Once at 9 am and then at 9 pm
Four times a day At 9 am, 1 pm, 5 pm, and 9pm
Three times a day At 9 am, 2 pm, and 9 pm
Bedtime At 9 pm
With meals At 8 am, 12 Noon, and 5 pm
With meals and at bedtime At 8 am, 12 Noon, 5 pm, and 9 pm
Injectable drugs Timing will depend on the first dosage

Further, schedules medications are of two types: Time-critical and non-time critical.

Time-critical medicines are those that you absolutely can’t miss. If you miss these medicines, you will have to take it within 30 minutes of the scheduled timing. Time-critical medicines include antibiotics, insulin, immunosuppressants, anticonvulsants, and pain medications.

Non-time critical medicines are those that can be taken within a wider time range – a shorter or longer interval between doses not affect the therapeutic range significantly. Medicines that need to be taken daily, weekly or monthly have a window of four hours within which you can take the medicine. Also, if you are taking a medicine every four hours, you have a window period of one hour even if you forget a dose. But the dose should not be much later than two hours. 2

Non-scheduled medicines

Medicines that are given at specific times or for specific purposes are non-scheduled medicines. These include: First doses or starting doses, statin doses, doses given before certain tests (while evaluating the drug levels in serum), drugs given as per need.

Standard timings for some of the most common medications

Statins: Statins are drugs used to control blood cholesterol levels and prevent heart attacks. Unless otherwise specified, statins are usually taken at bedtime.

Diuretics: Diuretics are given to control water and electrolytes in the body and prevent hypertension. These drugs are usually given in a twice a day schedule – at 9 am and 1 pm.

Antibiotics: Antibiotics kill or slow down the growth of pathogenic bacteria in the body. These are either given twice a day (at 12-hour interval), thrice a day (at eight-hour intervals) or four times a day (at six-hour intervals).

This article was written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health. For more articles like this, please visit myUpchar.com

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