From the Guidelines
The recommended aspirin dosage for preventing blood clots during long-haul flights is typically 75-325 mg taken once daily, starting 1-2 days before the flight and continuing until 1-2 days after arrival, with a preference for lower doses due to reduced bleeding risk, as suggested by studies such as 1 and 1. However, aspirin is not routinely recommended for all travelers. It should only be considered for individuals at higher risk of developing blood clots who don't have contraindications to aspirin use. Higher-risk individuals include those with previous history of blood clots, recent surgery, active cancer, pregnancy, hormone therapy, or known clotting disorders. Before taking aspirin, consult with a healthcare provider as it can cause side effects including stomach irritation, ulcers, and bleeding. Aspirin works by inhibiting platelets' ability to stick together, thus reducing clot formation. For many travelers, non-medication preventive measures are preferable, such as:
- Staying hydrated
- Avoiding alcohol and caffeine
- Performing leg exercises
- Walking periodically during the flight
- Wearing compression stockings, as recommended in 1 These approaches can effectively reduce risk without medication side effects. It's also important to note that the evidence for thromboprophylaxis to prevent VTE during travel is very limited, and specific studies of thromboprophylaxis during long-haul travel in patients with heart failure are lacking, as mentioned in 1. Therefore, the decision to use aspirin or other preventive measures should be made on an individual basis, taking into account the person's overall health and risk factors. In general, maintenance doses of 75 to 162 mg of ASA are preferred, as stated in 1, due to the lower risk of bleeding. Ultimately, the choice of aspirin dosage and the decision to use aspirin at all should be guided by the most recent and highest quality evidence, such as 1, which suggests that lower doses of aspirin are as effective as higher doses for preventing cardiovascular events, but with a lower risk of bleeding.
From the FDA Drug Label
Directions drink a full glass of water with each dose adults and children 12 years and over: take 4 to 8 tablets every 4 hours not to exceed 48 tablets in 24 hours unless directed by a doctor The FDA drug label does not answer the question.
From the Research
Aspirin Dosage for Long-Haul Flights
- The recommended aspirin dosage for preventing blood clots during long-haul flights is not explicitly stated in the provided studies, but a dose of 400 mg per day for 3 days, starting 12 hours before the flight, was used in the LONFLIT3 study 2.
- However, other studies suggest that low doses of aspirin, ranging from 100 to 300 mg per day, may be effective in preventing thrombosis 3.
- A more recent study found no difference in safety and effectiveness of aspirin dosed daily at 81 mg or 325 mg for secondary prevention of atherosclerotic cardiovascular disease 4.
Other Over-the-Counter Recommendations
- Wearing elastic compression stockings during long-haul flights is associated with a reduced risk of deep venous thrombosis 5.
- Passengers should be encouraged to use the muscle-vein pump regularly, ensure adequate hydration, and in some cases wear elastic compression stockings 6.
- Low molecular weight heparins may be considered in passengers at high risk of thrombosis 2, 6.
Considerations
- The risk of venous thrombosis increases with distance flown, and symptomless deep venous thrombosis may occur in up to 10% of long-haul airline travelers over 50 years of age 6, 5.
- Aspirin may have a protective role, but its efficacy in preventing venous thrombosis is much smaller than that of low molecular weight heparins 2, 6.
- The side effects of aspirin are mainly gastrointestinal and are dose-related 3.