Medical Error and the Medically-illiterate Patient

A fifty-seven year old lady came in 10 days ago  with a complaint of discomfort and feeling faint (light-headedness) for the previous two weeks. Now this lady has been on on my hypertension clinic follow-up for the last six months. For many years she had been treated by a general practitioner for hypertension and was prescribed with a beta-blocker to be taken once a day. She came to our clinic when she noticed that her headache was getting worse.

As per our medical protocol, patients detected to be hypertensive are fully investigated to determine their biochemical status with respect to their signs and symptoms. Prescription of medications is based on their allergy history and drug tolerability . Antihypertensive drugs are prescribed in stepwise manner, what is called "titration" of drugs and dosages. So with this lady she was started on a drug which unfortunately had induced a rapid heart rate. To counter that relatively common side-effect, another drug was added. Upon further monitoring, her blood pressure was still high for which another class of antihypertensive drug was further added. During this time she was coming to the clinic fortnightly. Her blood pressure eventually had stabilised in the normal range.

So it was rather out of the ordinary for her to come 10 days ago with the presenting complaints. Her blood pressure was on the high side and she admitted that she did not take the medications for the last few days because of the discomfort she had felt following the ingestion of the three drugs. Now I was stumped. What had happened to her in that short duration?

But as luck would have it, this very pleasant lady brought out her three sachets of medications and laid them out on my table. Yes, I always ask my patients to bring along all their medications especially when they are not as well-educated  so that I could explain explicitly which drugs could be causing their adverse effects if there were any. And also to reconcile with my medical notes.

Examples of drug sachets and a  blister pack that is inserted in  a sachet

Upon checking the sachets, I noticed that perindropril was interchanged with  amlodipine  sachet and atenolol  was in its original sachet..... Dear me! She had inadvertently changed the drugs and their respective sachets and was following the direction on the individual sachet  which was stated in terms of tablets rather than actual dosage in milligrams. And so this patient had mistakenly taken twice the dose of perindropril ( an ACE inhibitor) and half of the dosage of amlodipine and this combination had somehow depressed her blood pressure below the desired level and she became light-headed.

My medical notes for the month previously was 2mg (half a tablet ) of perindropril and 10mg (one tablet) of amlodipine. This has become a medical error  to me, the fact that the drugs were mixed up as the patient did not take precaution to keep her medications in the respective original sachet, And I also noticed that the sachet did not bear any name of the drug instead it was taken for granted that the patient would put back her drug in the right sachet, which did not happen in this case.

Having explained the slip-up. I  advised the patient to take each medication and then return each blister pack back immediately to its original sachet and then only take the other drug and do the same thing. Even if the Pharmacist has stated the name of the drug on the sachet, a medically  illiterate patient  has a higher risk of not being able to discern them.

It would have been a disaster had those drugs been more biologically active such as L-thyroxine or digoxin  due to their more immediate adverse effects. Due diligence on the part of the health personnel and the patients themselves is critical to prevent such consequences. 

Anyway, the lady patient came in today and her blood pressure was in the normal range and her discomfort and light-headedness had all but  disappeared and I am very pleased with the outcome. Indeed, it has been a lesson in medical error for all of us at the clinic. We certainly cannot take our patients for granted and any measures that can be taken to reduce this medical error would certainly  improve our patient care.