Which Medications Can Exacerbate BPH? Medication List Review

BPH is one of the most common causes of urinary retention. Drugs can and do exacerbate this problem. So, looking at this med list, which medications can exacerbate BPH? Here’s the medication review with a few questions that I would be looking into further.
• Proscar 5 mg daily
• Hydrochlorothiazide 12.5 mg daily
• Prednisone 10 mg daily
• Nexium 20 mg daily
• Flomax 0.8 mg twice daily
• Imdur 30 mg daily
• Aspirin 325 mg daily
• Metoprolol 25 mg twice daily
• Pseudoephedrine as needed
• Diphenhydramine 50 mg daily as needed for sleep
• Metformin 500 mg twice daily

As mentioned above, BPH with urinary retention can be exacerbated by medications and there are two medications that I would look at first, with the exception of the Flomax dose.

1. I would want to know this patient’s blood pressure and assess the Flomax dose first. If this dose if correct, I would be very nervous with this and assessing this with the patient and/or provider would be my top priority.

2. Anticholinergics can exacerbate BPH. In this case, you must figure out if this patient is using the diphenhydramine.

3. Pseudoephedrine can contribute to both BPH and hypertension. Assessing for dosing as well as frequency of as needed use would be very important.

Other items I would want to assess:

4. Prednisone use, length of therapy, and what diagnosis we are using it for. Long term systemic steroids should always be continually assessed due to lots of long term adverse effects (especially elevated blood sugars as this patient likely has diabetes – on metformin).

5. What else would you want to assess?

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  1. Felipe

    How about beta blockers? They reduce libido so is there an indirect correlation with BPH, potentially? Thanks Eric

  2. Mike Salamone, R.Ph.

    1. Is 0.8 mg of Flomax really more effective for this pt. than 0.4 mg? Sometimes double dose is not more effective, but leads to dizziness. Is he taking it 30 min. after largest meal of day to reduce dizziness? Potential dizziness with Imdur 30 (and HCTZ and Metoprolol as well). Proscar takes 6-12 months of continuous use to shrink the prostate. Where is he currently regarding that time span?

    2. Does he have any NTG available in case of chest pain? Does he have chest pain now w/Imdur 30?
    Does the Benadryl (and HCTZ somewhat) cause so much dry mouth that NTG S/L tabs will not dissolve readily? In which case, he would need NTG S/L spray.
    3. Benadryl, particularly at 50 mg, is inappropriate for any use in pts >65 yo. Trazodone 50 and Melatonin 5 mg (titrate both upward prn) would be much safer.
    4. Is ASA 325 mg really needed or will 81 mg suffice?

  3. Grant C

    Knock off the Benadryl and PSE. Too much Flomax. Then again, I’m seeing some prescribers combine selective and non-selective alpha blockers for urinary symptoms (e.g terazosin and tamsulosin)..interesting



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Written By Eric Christianson

June 15, 2016

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