Be aware that treatments such as Restasis may take up to six months to work and can cause burning and discomfort. Likewise, Xiidra takes around three months to alleviate symptoms, with many ...

But with Novartis failing to convince European regulators about the merits of Xiidra last year, and Allergan's ageing Restasis potentially facing generic competition, there’s a lot to play for ...

although it will compete with Allergan's older Restasis (cyclosporin). The US Food and Drug Administration initially rejected Xiidra in October last year, asking for an additional study.