Each week we will aim to bring out a concise email that provides 4-5 key pieces of information addressing a specific issue in clinical therapeutics.
This week: The Triple Whammy
The “Triple Whammy” is a vernacular term that has come to be used to describe the adverse renal effects associated with the combined use of an Angiotensin Converting Enzyme (ACE) inhibitors/Angiotensin Receptor Blockers (ARBs) with a diuretic + Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)
- The use of an ACE inhibitor or ARB in combination with a diuretic and NSAID is associated with a substantially increased risk acute renal impairment, sometimes resulting in frank renal failure. It is clear that particularly for elderly people, this situation is associated with a range of potentially serious adverse clinical outcomes such as electrolyte disturbances (e.g.hyperkalaemia), as well as potential for drug toxicity with medications that are renally cleared (e.g. lithium, digoxin).
- The risk of acute renal impairment is present whenever a diuretic is co-prescribed with these agents, but appears to be greater with loop diuretics such as frusemide. Even so, thiazide diuretics, including those incorporated in combination products may also substantially increase the likelihood of renal impairment.
- Similarly, all NSAIDs, including the Cox 2 selective agents such as celecoxib can contribute to impaired renal function in this context. The risk is compounded by other concurrent factors such as renal artery stenosis, or even dehydration.
- One situation to be aware of is when NSAIDs are used on a “when required” basis, meaning that the risk of renal impairment may be intermittent.
- Severe congestive heart failure often necessitates the co-prescription of ACE inhibitors/ARBs – NSAIDs cannot only impair function in this context, but may also exacerbate CCF. This being the case NSAIDs should usually be avoided for these patients.
Please consider these issues when preparing or interpreting RMMR reports or education sessions. Contributions of content or suggested topics are welcome and should be sent directly to firstname.lastname@example.org.