Abū Hurayrah reported that the Prophet (ﷺ) said, "If any one of you sneezes, let him say 'Al-ḥamdu lillāh', and his brother or companion should say to him 'Yarḥamuka-llāh' (may Allah have mercy on you); and when he says that, the one who sneezed should reply 'Yahdīkumu-llāhu wa yuṣliḥu bālakum' (may Allah guide you and set your affairs right)" (Sahih al-Bukhari 6224). If the sneezer does not praise Allah, the tashmīt is not said to him: Anas reported that two men sneezed in the presence of the Prophet (ﷺ) and he supplicated for one and not the other, and when asked he said, "This one praised Allah and that one did not" (Sahih al-Bukhari 6221; also in Ṣaḥīḥ Muslim). Sneezing is described as liked by Allah while yawning is from Shayṭān, so the yawner should suppress it as best he can, and no dhikr is legislated for it (Sahih al-Bukhari 6223).
Q&A · Dua & Dhikr
What should I say when I sneeze, and what should the person who hears me say?
Evidence — the daleel
Sahih al-Bukhari 6224 ṢaḥīḥSahih al-Bukhari 6221 ṢaḥīḥSahih al-Bukhari 6223 Ṣaḥīḥ
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.