At 4 months of pregnancy, most common coughs are due to mild infections or allergies, but it is important to choose medicines carefully. Start with safe home remedies like warm fluids, honey with warm water (if no diabetes), steam inhalation, and saline nasal sprays, which can help soothe the throat and reduce cough. If medicine is needed, doctors may prescribe pregnancy-safe options such as simple cough syrups or antihistamines, depending on your symptoms, but avoid taking any over-the-counter medicines on your own. Always check with your doctor before starting any medication to ensure it is safe for you and your baby. Seek medical advice if the cough is severe, lasts more than a few days, or is associated with fever, breathlessness, or chest pain.