Favourite: an Islay or Isle of Skye whiskey
Most effective: Stilnox
Most healthy: Camomile tea

The first two are mutually exclusive. The third can be combined with either of the other two if you want to feel better about including the healthy component while ensuring effectiveness. Option 3 on its own is least expensive - but not necessarily best value for money .

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For 1 and 2, best test the effectiveness before travel in a controlled environment to ensure dosage is correct. For 1, this may require detailed analysis over an extended period.
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