A new report says some refugees have resorted to returning to Syria to receive the treatment they need. Amnesty International says a shortfall in international support has left many Syrian refugees in Lebanon unable to access crucial medical care SIA reports.
More than one million Syrians have fled to Lebanon to escape the fighting in their country.
The UN says there are now 2.7 million registered Syrian refugees and the number is still rising.
Large numbers have been taken in by Turkey, Jordan, Iraq, Egypt and other countries, but Lebanon is bearing the biggest burden of all.
In March the Lebanese foreign minister said the crisis was "threatening the existence" of his country. The UN has appealed to international donors for $4.2bn (£2.4bn) for Syrian refugees in 2014 but has only received 24% of that sum.