Clinical Therapeutics Flashcards

A patient with chronic heart failure is being managed with ramipril and bisoprolol. Despite optimal doses, they remain symptomatic (NYHA class III). According to NICE, which additional medication should be considered?

Answer: Spironolactone (or eplerenone)

NICE recommends adding a mineralocorticoid receptor antagonist (MRA) such as spironolactone or eplerenone for patients with heart failure with reduced ejection fraction who remain symptomatic despite optimal ACE inhibitor and beta-blocker therapy. This is established step 3 in the heart failure treatment pathway.

Which of the following medicines requires therapeutic drug monitoring (TDM) due to its narrow therapeutic index?

Answer: Lithium

Lithium has a very narrow therapeutic index — the difference between a therapeutic dose and a toxic dose is small. Regular serum lithium monitoring is essential (target range 0.4-1.0 mmol/L for maintenance). Toxicity can cause renal failure, seizures, and cardiac arrhythmias.

A patient with COPD is prescribed a LAMA/LABA combination inhaler. They continue to have frequent exacerbations. According to NICE, what should be considered next if the patient has features suggesting asthmatic/eosinophilic disease?

Answer: Escalate to triple therapy by adding an inhaled corticosteroid (ICS)

NICE recommends escalating to triple therapy (LAMA + LABA + ICS) for COPD patients with asthmatic features or raised eosinophils who continue to exacerbate despite dual bronchodilator therapy. The ICS component addresses the eosinophilic inflammation driving the exacerbations.

A patient on warfarin presents with an INR of 8.5 with no active bleeding. According to NICE/BNF guidance, what is the most appropriate management?

Answer: Withhold warfarin and give oral vitamin K 1-5mg; recheck INR in 24 hours

For an INR above 8.0 with no bleeding, the BNF recommends stopping warfarin and giving oral phytomenadione (vitamin K) 1-5mg. The INR should be rechecked after 24 hours. IV vitamin K and fresh frozen plasma are reserved for cases with major bleeding.

A newly diagnosed asthma patient is prescribed a salbutamol inhaler. They are using it four times per week. According to the BTS/SIGN stepwise approach, what should happen next?

Answer: Add a regular low-dose inhaled corticosteroid (ICS)

Using a reliever inhaler three or more times per week indicates uncontrolled asthma. BTS/SIGN guidelines recommend stepping up to a regular low-dose ICS (e.g., beclometasone 200-400 micrograms/day) at Step 2. A LABA should never be used without an ICS in asthma.

Which of the following is a recognised serious interaction between clarithromycin and simvastatin?

Answer: Increased risk of rhabdomyolysis due to CYP3A4 inhibition

Clarithromycin is a potent CYP3A4 inhibitor. Simvastatin is extensively metabolised by CYP3A4. Co-administration significantly increases simvastatin plasma levels, greatly increasing the risk of myopathy and rhabdomyolysis. This combination should be avoided — simvastatin should be suspended during clarithromycin treatment.