1. The use of elastic compression stockings (such
as JetSox, approved by the TGA; Scholl Anti-DVT Flight Socks; OAPL Travel
Stockings or Tyco T.E.D.Stockings). In moderate risk patients graduated compression stockings are highly effective, and given that they are cheap, easy to use, and have negligible adverse effects their use should be promoted widely in these patients.
2. The use of oral aspirin.
3. The non-use of sleeping tablets.
All the containers must be sealed in a transparent, one-litre plastic bag. You are only allowed one plastic bag. Any transparent resealable bag of one litre capacity or less is allowed.
You may still carry on board prescription medicines. Baby products and non-prescription medicines that you need for the flight are also allowed. Proof of need may be required.
Passengers may carry small quantities of liquids, but only within separate containers each of which with a capacity not greater than 100ml.
The US has elevated its threat condition level to Red (Severe) for all commercial flights from the UK, and to Orange (High) for all other international flights and all domestic commercial aviation. 
2. Exercise calf muscles while seated every half hour or so. 
Pressure within the middle ear must be maintained by an open eustachian tube (facilitated by swallowing, yawning, chewing), which connects the middle ear to the back of the nose. This does not happen when the tube is blocked by infection (eg a cold, middle ear infection) or allergic problems (eg hay fever) and severe pain can result as a consequence of the increased pressure. Oral decongestants of nasal sprays might clear the eustachian tubes and prevent this pain, but passengers with recent intraocular eye surgery, ear or sinus surgery or current sinusitis or middle ear infection are advised to delay their flight until recovered.