Yes. The European Health Insurance Card (EHIC) entitles you to reduced cost, sometimes free, medical treatment when you're travelling in the European Economic Area (countries within the EU plus Iceland, Liechtenstein and Norway). You may have to contribute to your medical costs and it will not cover all costs, e.g. it will not cover the cost of repatriation to the UK.
It also does not provide for any other risks you may encounter such as cancellation of your trip, travel delays, lost baggage etc.
If you use an EHIC, any medical expenses claim will not have the excess applied.
To apply for an EHIC, visit www.ehic.org.uk or pick up an application form at your local Post Office.
If Britain leaves the EU without a deal, then the EHIC card will no longer be valid. Even if Britain remains in the EU or agrees a deal, the EHIC will not provide the same benefits as travel insurance. In the event of a no deal Brexit, then the excess will be payable on all medical claims as the EHIC cannot be used.