((إِذَا عَطَسَ أَحَدُكُم فَلْيَقُلِ الْحَمْدُ لِلَّهِ، وَلْيَقُلْ لَهُ أَخُوهُ أَوْ صَاحِبُهُ: يَرْحَمُكَ اللَّهُ، فَإِذَا قَالَ لَهُ: يَرحَمُكَ اللَّهُ، فَلْيَقُلْ: يَهْدِيكُمُ اللَّهُ وَيُصْلِحُ بَالَكُمْ)).
Transliteration
(When one of you sneezes he should say:(Alhamdu lillah.) and his brother or companion should say to him: (Yarhamukal-lah.) and he (i.e. the one who sneezed) replies back to him:(Yahdeekumul-lahu wayuslihu balakum.))
Translation
(When one of you sneezes he should say:(All praise if for Allah.) and his brother or companion should say to him: (May Allah have mercy upon you.) and he (i.e. the one who sneezed) replies back to him:(May Allah guide you and rectify your condition.))
Source
Hisnul Muslim (Fortress of the Muslim), No. 188 — chapter “Invocation for sneezing”. hisnmuslim.com
Related Duas
((يَهْدِيكُمُ اللَّهُ وَيُصْلِحُ بَالَكُمْ)).
(May Allah guide you and rectify your condition.)
Hisnul Muslim · No. 189
((أَعُوذُ بِاللَّهِ مِنَ الشَّيْطَانِ الرَّجِيمِ)).
(I take refuge with Allah from the accursed devil.)
Hisnul Muslim · No. 193
((الْحَمْدُ لِلَّهِ الَّذِي عَافَانِي مِمَّا ابْتَلاَكَ بِهِ، وَفَضَّلَنِي عَلَى كَثِيرٍ مِمَّنْ خَلَقَ تَفْضِيلاً)).
(All praise is for Allah Who saved me from that which He tested you with and Who most certainly favoured me over much of His creation.)
Hisnul Muslim · No. 194