Dreaming of sneezing signifies re-evaluating certain issues that you have doubts about. It indicates an acknowledgment of the truth. When you sneeze in a dream, it symbolizes the hesitation and uncertainty in your mind. Often, it represents the process of accepting some truths in your life that may be significant for you.
From Imam Muhammad Ibn Seerin's Dictionary of Dreams According to Islamic Inner Traditions â entry "Sneezing" (page 399).
Sneezing in a dream means reassessing something about which one had doubt. Thus, sneezing in a dream could mean acknowledging the truth, and that is why people's common reply is "God bless you." Sneezing in a dream also could mean the death of a sick person, or experiencing agony, distress, adversities, or facing a disturbing problem. If one who is experiencing such trials sees himself sneezing in a dream, it means that the time has come to dispel them. If a poor person sneezes in a dream, it means that he may wake up to find that help is coming his way. Sneezing in a dream also could mean paying one's debts, or recovering from a cold or a nasal congestion, or it could mean exasperation, fury, rage, anger, or frowning. If one sneezes with force in his dream, it means that he should beware of a strong enemy and the possibility of suffering losses at his hands.
Note: Islamic dream interpretation depends on the dreamer's circumstances and state. This is a general guide drawn directly from the source book.