Hello, Sinus complains are a very common complaints to my clinic and if equiped with right information , sinusitis can be taken care of . The pungent odor that your father has noticed is usuall in cases of long term sinus infection .As the secretions in the sinus pools, it causes bactaria to grow which leads to a bad odor as the time pass. So i would suggest to use an oral antihistamin , and a decongestant nasal spray which will clear your sinus . Continue this treatment for a period of 5 to 7 days. As the secretion decrease and more clear fluid starts coming you will note that the odor will also be over. If this problem still persists that i would advise to visit your physician who will advise you an antibiotic to get rid of the bactarias in case of long standing sinus infection Having said that it is very important to note here that with sinus infection , ear infection is a common phenomenon and ear infection do emit very bad smell. So make sure you are not having ear discomfort or reduced hearing in both ears. If you do then you will have to visit your ENT specialist who will examin for any ear problems. I hope the answer was helpful. If you have any further questions , fee free to contact us in writing. Regards Dr Talal Hussain