Case Studies

Chapter 22: Dealing with adverse drug reactions

Mr Brown is an 81-year-old man admitted to a geriatric ward with an episode of collapse on 2^nd March. He had been feeling well, and then had an episode of loss of consciousness with no warning. His wife heard him fall to the floor at approximately 11am. She says he came round within a minute, and had no confusion or drowsiness afterwards. There was no indication of tongue biting or incontinence. She then called an ambulance. The ambulance crew noted mild bradycardia (40 bpm) but nothing else at the time. On further history, you find that this has not happened before. Mrs Brown says her husband was started on new tablets for dementia 3 weeks ago (7^th January). His past medical history is reported as Alzheimer's, IHD, OA hips. Current medications are: rivastigmine 1.5mg bd, aspirin 75mg od, simvastatin 20mg od, bendroflumethiazide 2.5mg od, co-codamol 2 tabs prn, oxybutynin 2.5mg bd. Mrs Brown says her husband does not take any over-the-counter medicines, except sometimes a cream for his joints.

There is nothing abnormal to find on examination.

An ECG shows sinus rhythm at 50 bpm, with first degree heart block only. Other investigations are unremarkable. Your consultant asks for a 24 hour Holter monitor. This is reported as showing episodes of second degree heart block. Your consultant feels it is likely that a bradyarrhythmia has cause the episode of syncope.

You are asked to look up rivastigmine as a possible cause of Mr Brown's heart block and find that bradycardia and syncope are listed as side effects. The medication has a black triangle and therefore your consultant asks you to fill in a yellow card to report this possible adverse effect. In the meantime, the rivastigmine is stopped and the following week a repeat Holter monitor shows no further episodes of heart block and a heart rate of 60 bpm.

• Complete the yellow card.

  Show Answer

  Model answer:
  

  

  Case Study Figure 22