Amr (bin Dinar) (may Allah have mercy on him) narrates that when water began to come from the eyes of Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) (due to illness), he wanted to have it treated. He was told: You will have to pray lying down for so many days as a precaution. So he refused it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3683