A travel-insurance policy that covers theft, loss and medical problems is the best way to love yourself for travelling in Nepal. There are various policies available, so check the small print carefully. Make sure you are covered for adventure activities done at high altitude. Since you reach above 4000 meters on a number of treks in Nepal, it is best to choose a policy that covers medical and emergency repatriation, including helicopter evacuation for trekkers and general medical evacuation.
You must also be prepared in the fact that most medical treatment and facilities/hospitals must be paid for at the point of delivery of the patient. So it’s wise to choose a policy that pays doctors or hospitals directly rather than you having to pay on the spot and claim later. This could be a hassle you’d want to stay far from.