Clinical Med List Review – Primidone

78 year old male recently admitted to the hospital with a fall and likely hip fracture. He has had some lethargy and confusion lately as well. Previous falls have been noted as well. Current medication list of:

  • Calcium and Vitmain D twice daily
  • Proscar 5 mg daily
  • Tamsulosin 0.4 mg daily
  • Primidone 500 mg QID
  • Aspirin 325 mg daily
  • Enalapril 5 mg daily
  • Tylenol 500 mg twice daily as needed
  • Senna 1-2 tabs as needed
  • Artificial tears as needed
  • Percocet 5/325 1-2 tablets as needed for pain
  • Gabapentin 100 mg at night
  • Propranolol 80 mg twice daily
  • Benadryl 50 mg at night for sleep
  • Metoprolol 25 mg twice daily

Quite a few problems to note with this medication list. One of the major problems of polypharmacy that I see is things just have a much greater risk of being overlooked. If you have a patient on two medications, it is pretty easy to rule out medication related issues in a minute or two.  When patients are on 10, 20, 30+, things just slip through the cracks.

The first thing I’m going to pull out here which is absolutely terrifying to me is Primidone. If this is a medication you don’t know much about, I’d suggest you take a look at it. This is a ridiculously high dose that should scare the pants off you.  I can’t even recall a dose half that size in any other patient I’ve seen before. I would suspect the diagnosis is essential tremor, as usually that’s the diagnosis, but it is an old antiepileptic. In any case, this dose likely needs to be reduced or we need to at least check a level with a phenobarbital level as primidone is converted to phenobarb in the body.

Second – Two Beta blockers.  Propranolol makes me lean toward primidone being used for tremors, but would have to look into that further.

Third – notice the “trigger” medication as I call them. Those medications that likely are treating side effects of other medications (prescribing cascade). We have Senna, Artificial Tears, as well as medications for BPH/urinary retention. Remember that these symptoms/medications scream anticholinergic effects.

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  1. robert bliss

    appreciate the insights you give us

    • chri1599

      I’m not perfect, but getting better 🙂

    • Bill Bidwell

      elegant explanation….well done!

      • chri1599

        Thanks Bill!

  2. chri1599

    Mohammed, I just resent it to the email left in the message, please let me know if didn’t get it, maybe check junk or spam email? – Thanks for subscribing! – Eric

  3. Lindsey

    Don’t forget high dose diphenhydramine at bedtime for anticholinergic side effects!


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Written By Eric Christianson

December 3, 2014

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