Dry, winter and/or high altitude environments increase the risk for dehydration.Many people who venture into the backcountry turn to their old friend ibuprofen when their muscles get sore or in the case of injury. Wilderness medicine training courses such as Wilderness First Aid, Wilderness First Responder and Wilderness EMT along with other wilderness medicine practitioners often recommend using ibuprofen as an adjunct to rest, ice, compression and elevation for the treatment of minor musculoskeletal injuries. In the backcountry, ibuprofen is commonly taken for pain relief (analgesic), fever reduction (antipyretic) and as an anti-inflammatory. Ibuprofen, along with other common over the counter (OTC) analgesics such as aspirin and naproxen sodium, belongs to a class of drugs called non-steroidal anti-inflammatory drugs or NSAIDs.The mechanism of action for Ibuprofen is to inhibit the cyclooxygenase enzyme (COX) which is an integral component of the arachicdonic acid metabolic pathway that results in the production of chemical mediators called prostaglandins. Prostaglandins are a group of ubiquitous biochemicals that have a diversity of homeostatic regulatory affects in the body including pain perception, inflammation and fever production.Prostaglandins are also involved in many other aspects of the body’s attempts at maintaining homeostasis including healing of injured tissue, blood pressure regulation, renal function and fluid balance. In general, in a healthy population, OTC analgesics are considered to be safe when taking the recommended dose for the treatment of minor aches, pains and fever.For those who spend time in activities and/or environments that increase the possibility of musculoskeletal injury and/or dehydration , two particularly concerning side effects of taking NSAIDs are delayed tissue healing and damage to the kidneys.
Pain relief and decreasing inflammation is an important part of the healing process and may allow for earlier rehabilitation and increased usability in the case of musculoskeletal injury. Several studies suggest that long term use of NSAIDs may interfere with healing associated with musculoskeletal injury leading to delayed tissue regeneration.There may be some benefit from acute use of NSAIDs in musculoskeletal injury, but long term use shows no benefit or greater negative affects with regard to recovery time, muscle and connective tissue regeneration and regaining strength.
The data on the renal affects of ibuprofen are concerning in a wilderness setting due to the increased possibility (probability) of hypovolemia due to dehydration. A majority of the studies suggesting renal complications with OTC ibuprofen examined susceptible populations such as those with renal or liver dysfunction, congestive heart failure or dehydration. It is the last of these that is of the most concern in the backcountry.The level of dehydration that puts one at risk for renal complications with even a one time, OTC dose of Ibuprofen is not well defined. There are several studies indicating that COX inhibitors (such as Ibuprofen) also inhibit renal prostaglandins which results in a decrease blood flow to the kidneys and associated decreased renal function. In an already compromised kidney, such as in dehydration and volume depletion, this could lead to fluid and electrolyte disturbances, nephritis and in severe cases renal failure.The good news is that for a majority of cases, cessation of the offending NSAID results in reversal of the renal adverse affects.
Recommended doses for OTC Ibuprofen:
Analgesia/antipyretic:200 -400 mg every 4-6 hours – not to exceed 1200 mg/ day as needed
Anti-inflammatory: 400 – 800 mg, every 6-8 hours- not to exceed 3200 mg/day , for no longer than two weeks.
To minimize the possibility of renal damage, it would be advisable to avoid taking ibuprofen while in a dehydrated state. It would be highly advisable to rehydrate properly prior to taking NSAIDs and to drink plenty of fluids along with the medication. Also avoid chronic use of OTC pain medications unless prescribed by a physician. Seek medical attention for pain, inflammation or fever that does not improve or becomes worse.
Adverse effects:the most common adverse reactions to ibuprofen are gastro-intestinal upset.Other symptoms include edema and fluid retention.Individuals who experience these (or other) side effects should discontinue the ibuprofen and seek medical advice.
References
Almekinders, LC . Anti-Inflammatory Treatment of Muscular Injuries in Sport – an update of recent studies. Sports Med (1999); 28(6): 383-388
Rainsford, KD.,Roberts, SC.,& Brown, S. Ibuprofen and Paracetamol: Relative Safety in Non Prescription Doses. J. Pharm. Phamacology (1997); 49:345-376.
Ulinski T, Guigonis V, Dunan O, Bensman A. Acute renal failure after treatment with non-steroidal anti-inflammatory drugs. Eur J Pediatr. (2004) Mar;163(3):148-50.
Whelton, A. Renal Effects of Over-the-Counter Analgesics. J. Clin Pharmacol. (1995); 35:454-463
