Unfortunately, getting a travel insurance policy will not give you much protection in terms of health insurance. Travel insurance policies almost unanimously exclude pre-existing conditions from medical coverage.
If you have supplemental health insurance from a Swiss health insurance company, check whether you policy provides travel health insurance (many do). Here too, however, there may be limitations on coverage for conditions which existed ahead of a trip.
It is worth noting that the basic health insurance coverage you get with your compulsory Swiss health insurance policy does cover you outside of Switzerland as well. The main condition for using this coverage is that you do not go abroad for the purpose of receiving medical treatment. Medical emergencies abroad are covered – up to double the cost of receiving the same treatment in your canton of residence.
A list of the coverage you receive from your compulsory Swiss health insurance policy is available here:
http://www.moneyland.ch/en/basic-swiss-health-insurance-costs-covered-overview