Dr. Patricia Farrell on Medika Life

Is There an Effective Time of Day to Take Your Medication or Not?

The prescription says BID, TID or PRN, but is there a time of day instead of a number of hours between doses, to take your medication? Science thinks there may be.

The prescription indicates you should take your medication once a day (QD), twice a day (BID), three times a day (TID), or when needed (PRN), but is this your most effective dosing schedule? Will you realize optimum benefit from the medication if you space it out a specific number of hours or is there something missing in the prescription — something unique to YOU? Research is now revealing that this one-size-fits-all approach to medication dosing flies in the face of your body’s individual metabolism.

How many physicians or prescribers have ever thought that there is an individual time of day for each person to take their medication? It’s not the number of hours between the doses but when the doses should be taken, and that is a matter of our individual circadian rhythms. How could that be determined?

The dawn of circadian rhythms in medicine is here and it’s not confined to sleep medicine, but to all of medicine where it applies, albeit there is a paucity of knowledge in medicine about its effects.

We now know that one research effort that looked at 106 clinical trials over 50 years found that 75% of the studies discovered treatment efficacy or toxicity was highly dependent on dosing time across a number of conditions which included hypertension, cancer, asthma and arthritis.

The number of medical conditions that would be affected by dosing and circadian rhythm is obviously not limited to these few disorders and, most probably, affect the whole of medicine and every single medical disorder.

To disregard this natural schedule is not practicing medicine effectively for the benefit of the patient. Scribbling out prescriptions without this important knowledge is like trying to keep chalk drawings on a sidewalk in a thunderstorm.

Our molecular clock runs on a 24-hour circadian rhythm in cardio, metabolic, endocrine, immunologic, and behavioral functions. This 24-hour clock has been questioned by sleep medicine experts who believe it is a bit more than that but less than a 25-hour clock.

More Than Sleep Hygiene

One aside note here about your sleep environment. You’ve heard about keeping the room cool, having blackout shades or heavy window coverings, but that’s part of sleep hygiene, not what I’m addressing.

ANY amount of light in the room while you sleep is disruptive to possibly ALL of those multiple body clocks that run your entire body. We’re not concentrating here on daytime sleepiness or alertness while you work.

It doesn’t matter if it’s a night light, a TV screen, an illuminated alarm clock, the light on a computer surge protector — anything is disruptive. What might you do? Consider whether a sleep mask would be an idea to make a part of your sleep preparation.

Besides the consideration of eliminating light as you sleep, is there a specific dosing time of day for medications? Researchers indicated that “only four out of the 50 currently most prescribed drugs have FDA labeled time-of-day dosing recommendations,” and (WHO) the world health organization’s list of essential medicines, does not mention dosing time.

It is more than curious that while some experts are considering dosing time important, others fail to recognize it. Maybe they never heard about it in medical school, but don’t they have an obligation to keep up with the research, and doesn’t the FDA and the pharmaceutical firms bear some responsibility here, too? The question of circadian regulation has been addressed, and there is a belief that every peripheral tissue in mammals has a local clock for that specific tissue.

Of course, this tissue issue makes medication dosing and timing for patients important and difficult unless we have a universal timetable from which to extract the optimum time for each individual’s medication dosing. A brain component of the hypothalamus is the central switching station, but each “clock” still has to synchronize to it. Computers and algorithms would seem to be the way to solve this dilemma, and yet I have failed to find anything that has offered that solution.

Whether you should be taking your cholesterol medication in the morning, at noon or afternoon is an important issue. It’s the same with every medication you take, with the possible exception of insulin that is required to keep glucose levels within certain parameters no matter the time of the day. Suppose cancer medications would be most effective at noon rather than in the morning, but they’re still given in the morning, wouldn’t that make a difference in your health?

Is the lack of consideration of optimal dosing time of day reducing a medication’s potential to remediate some disorder? The science suggests that is exactly the case.

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Pat Farrell PhD
Pat Farrell PhDhttps://medium.com/@drpatfarrell
I'm a licensed psychologist in NJ/FL and have been in the field for over 30 years serving in most areas of mental health, psychiatry research, consulting, teaching (post-grad), private practice, consultant to WebMD and writing self-help books. Currently, I am concentrating on writing articles and books.


Medika Editor: Mental Health

I'm a licensed psychologist in NJ/FL and have been in the field for over 30 years serving in most areas of mental health, psychiatry research, consulting, teaching (post-grad), private practice, consultant to WebMD and writing self-help books. Currently, I am concentrating on writing articles and books.

Patricia also acts in an editorial capacity for Medika's mental health articles, providing invaluable input on a wide range of mental health issues.

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