Last year, I skeptically tried an herbal formulation called "No Jet Lag", which is a tablet. You take two before takeoff, two before landing, and one at regular intervals during a long flight. I left JFK 6:30pm to LHR, arrivng 6:30am; left 8:45 for TLV, arriving around 3:30pm local time (8:30am NY time), picked up a car, drove 30 minutes to the office, and went right to work, with no loss of energy and no tiredness. I have become a believer, and I encourage others to try this. I have no affiliation with the product or company. It can be bought on line, and through health food type stores.