Sayyiduna Abu Hurayrah (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "Whoever is overcome by vomiting while he is fasting, there is no making up due from him; but if he made himself vomit, then he must make up the fast, which he should perform."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8027