Tonya L. Breaux-Shropshire, PhD, DNP, FNP, MPH-
Blood Pressure Medication Taking: Splitting the Dose or Not.
One of my Facebook friends had an interesting question she asked”
“For those on nefedipine xr 60 mg..do you take one (30 mg) pill in the morning and one at night or do you take them both at the same time..also, how long did it take for you to see an improvement with this med?”
I told her “It’s best to take it how it’s prescribed (i.e., depends on how your doctor wrote the prescription). It makes a difference.”
She said, “He had me on one pill a day ..but at my follow up..he said to go up to 60 mgs…I’ve been taking both ( 30 mg) tablets at once, but my mom said I am supposed to take it day and at night( that’s how she takes hers)….I can’t ask my doctor because he’s close until Wednesday”
I said, “In that case, you may call your doctor’s office and ask whoever is covering for your doctor. Otherwise, call your pharm D for advice, but it might depend on your bp values in the morning and at night and your target goal.
The “er” or “xr” is the extended-release intended to last for 24 hours and splitting the dose will likely reduce your bp less for at least until you take the night dose than taking both at the same time…if that makes sense.”
“If your blood pressure is generally moderate to severe, splitting up the dose could allow your bp to be too high until you take the nighttime dose. However, if your bp usually spikes at night and is lower during the day, splitting up the dose might be best.”
“That’s why it’s best to monitor your bp in the morning and evenings for at least 7 days and share it with your doctor or pharm d to determine what’s best for you.”
My final response was “From your post above, it sounds like you are taking it as he stated but my intent was to encourage you to be sure by verifying with your doctor.”
The question was a good one. The best answer depends on several factors as stated above and what the doctor wanted her tarket goal to be. Also, daytime versus nighttime dosing might need to be considered.