Time to dispense with inconsistent dosing instructions?

Here's a little brainteaser. Let's say you were prescribed two medications with the following dosing instructions:

• Take 1 tablet by mouth twice daily for 10 days
• Take 2 tablets by mouth every 12 hours.

How would you schedule your doses?

When a similar question was posed in a recent study, nearly 8 in 10 people said they would take the drugs four separate times a day. But the easiest way would be to combine the doses, as the instructions are similar--"every 12 hours" is another way of saying "twice daily." This would mean a simpler medication schedule, making it less likely that you'd forget a dose. But this is far from obvious when looking at the instructions.

This is what many older people face each day. Americans over age 65 fill an average of 20 prescriptions a year. That's a lot of doses to juggle. And, because of vague and inconsistent wording on the prescriptions, they may adopt unnecessarily complex dosing schedules, not realizing that many medications can be taken at the same time.

To help, the Institute of Medicine has proposed a universal medication schedule (UMS), which would simplify dosing instructions. For most prescriptions, the UMS would dispense with wording such as "take every 12 hours" in favor of four dosing timeframes: morning, noon, evening, and bedtime. However, there has been resistance to the proposal, as it would mean a big change in prescribing practices, and some critics have wondered how much it's needed.

This brings us back to the study mentioned above. To learn more about how people cope with complicated dosing schedules, researchers asked 464 older people (the average age was 63) how they would take a hypothetical combination of drugs. Participants were given seven medications, each with its own dosing instructions. They were then asked to distribute the drugs in a medicine box with 24 slots, one for each hour of the day.

The most efficient schedule involved taking the medicines four times daily. But, on average, people arranged to take the medicines six times a day. Only 15 percent organized the medicines into four or fewer dosing sessions, and some went as high as 14 separate doses.

Although the drug regimen in the study was hypothetical, the apparent confusion over the dosing instructions was not. This suggests many older people may be unnecessarily complicating their dosing schedule, which could mean missed or incorrect doses, and less effective treatment.

What you need to know. If you take medications several times a day, you could talk to your doctor or pharmacist about how to streamline your dosing schedule. Taking medications at the same time could simplify your life and help to ensure you get the full benefit of your treatment. If you're concerned that it might not be safe to take two or more of your medications together, be sure to check with your doctor or pharmacist.

--Sophie Ramsey, patient editor, BMJ Group

 ConsumerReportsHealth.org has partnered with The BMJ Group to monitor the latest medical research and assess the evidence to help you decide which news you should use.

Read more on how to prevent medication mistakes.

—Lisa Gill