Benzodiazepines Should Generally Be Avoided for Air Travel
The available evidence strongly recommends against using benzodiazepines (sleeping pills) for air travel, particularly for passengers at increased risk of venous thromboembolism (VTE). 1
Key Recommendation from Guidelines
The British Thoracic Society guidelines explicitly state that passengers at slightly increased risk of VTE should avoid sleeping pills during flights 1. This recommendation applies to passengers over 40, those who are obese, have varicose veins, or have had recent minor surgery. The rationale is that benzodiazepines promote immobility during sleep, which increases DVT risk when combined with the confined space and reduced mobility of air travel.
Why Benzodiazepines Are Problematic for Flying
Immediate Concerns:
- Paradoxical physiological activation: Research demonstrates that alprazolam (a commonly used benzodiazepine) actually increases heart rate (114 vs 105 bpm) and respiratory rate (22.7 vs 18.3 breaths/min) during flight stress, despite reducing subjective anxiety 2
- Impaired therapeutic effect: The same study showed that benzodiazepine use during exposure to flying led to increased panic attacks on subsequent flights (71% vs 7%) and higher anxiety (8.5 vs 5.6) 2
- Respiratory depression risk: Recent evidence shows benzodiazepines cause slight reductions in PaO2 during sleep, which is particularly concerning at altitude where oxygen partial pressure is already reduced 3, 4
VTE Risk Enhancement:
- Benzodiazepines promote prolonged immobility during sleep
- Passengers cannot maintain normal sleeping positions in aircraft seats
- This combination significantly increases DVT/PE risk 1
If Medication Is Absolutely Necessary
For short-haul flights requiring sleep aid: If a benzodiazepine must be used despite the above concerns, midazolam 7.5 mg has the most specific evidence for managing transient insomnia related to time zone changes 5. However, this should only be considered for:
- Patients without VTE risk factors
- Short-term, intermittent use only (single dose)
- Flights where the patient can maintain some mobility
Critical contraindications:
- Any VTE risk factors (age >40, obesity, varicose veins, recent surgery, family history of VTE, pregnancy, hormone therapy, previous VTE, thrombophilia, malignancy, recent stroke) 1
- Respiratory disease (COPD, asthma, OSA) - guidelines specifically recommend avoiding sedatives before and during flight 4
- Alcohol consumption planned during flight (absolute contraindication) 1
Safer Alternatives
Instead of benzodiazepines:
- Maintain mobility: Walk the aisles regularly, perform leg exercises while seated
- Avoid alcohol and caffeine 1
- Compression stockings for those with any VTE risk factors 1
- Aspirin for moderate VTE risk (family history, recent MI, pregnancy, recent surgery) 1
- Behavioral interventions for flight anxiety rather than pharmacological sedation 2
Common Pitfall to Avoid
Do not prescribe benzodiazepines simply because a patient requests them for flight anxiety. The evidence shows this approach backfires - it increases physiological stress during the flight and worsens anxiety on subsequent flights through interference with natural habituation 2. Additionally, the VTE risk from immobility outweighs any subjective anxiety relief, particularly given the paradoxical physiological activation these drugs cause during acute stress.