You seem to be suffering from a bacterial infection of upper respiratory tract
and you will need an antibiotic. Antibiotics that are safe during pregnancy include amoxicillin
, ampicillin, clindamycin
and penicillin. You can have steam inhalations to help reduce the thick secretions. You can try local applications like nilgiri oil and ayurvedic preparations which do not have much of systemic affect. Please consult your doctor for further advice. Take care.