Brief Answer: Penicillin group of antibiotic are preferred... Detailed Answer: Hi, A stuffed sinus stays that way until it is cleared or gets resorbed. If your sinus openings are very narrow and congested, you are going to suffer from recurrent / chronic sinusitis. So the priority is to clear the stuffiness. At this instance, it would be extremely difficult to predict the nature of infection without help of laboratory test. If I were the treating doctor I would have ordered for hemogram and swab from throat and nasal secretions to confirm the nature of infection and type of bacteria. If antibiotic use is essential, I prefer to use pencillin group of drugs like amoxicillin + clavulanic acid combination three times a day for 5-7 days. I prefer this penicillin over doxycycline due to its bactericidal effects (doxy has bacterostatic effects only). That being said, FDA has approved doxycycline to treat upper respiratory tract infection. You can continue using doxy as instructed for 3-4 days. If symptoms don't improve aforementioned tests are warranted. In addition, I also recommend that you use steam inhalation three time a day to clear up congested sinus openings. As described initially that is going to be the priority. You should also use nasal decongestant or antihistamines for few days to dry up secretions. You can also consider visiting an ENT surgeon and consider surgical procedure to prevent sinus issues or atleast reduce the intensity of sinus problem in future. Hope I have been helpful. Let me know if you need clarifications. Regards

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