Hello and thanks for posting the query.
Antibiotics are required in treatment of acute sinusitis in only 1% of cases.
Sinusitis can be cured by simply following some home care methods like

1. Promoting drainage of mucus by Drinking plenty of water and hydrating beverages such as hot tea.
Inhale steam two to four times per day by leaning over a bowl of hot water (not while the water is on the stove) or using a steam vaporizer. Inhale the steam for about 10 minutes. Taking a hot, steamy shower may also work. Mentholated preparations, such as Vicks Vapo-Rub, can be added to the water or vaporizer to aid in opening the passageways.
2. Thinning the mucus by  Expectorants. These are drugs that help expel mucus from the lungs and respiratory passages. They help thin mucous secretions, enhancing drainage from the sinuses. The most common is guaifenesin (contained in Robitussin and Mucinex, for example).

3. Relieve pain: Pain medication such as ibuprofen can reduce pain and inflammation. These medications help to open the airways by reducing swelling. 

4. Using nasal saline or decongestants for few days.

You do these for 2 weeks and You shall be all right with these measures however if you feel that your symptoms are worsening,then you may have to contact an ENT specialist for proper investigation and treatment.
I hope to have answered your query however you may revert to me for any further query.
Thanks and best of luck.

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Hello
Instead of tulsi seeds you better use tulsi leaves which can help in coughs,sore throat and respiratory disorders.
Coughs: Tulsi is an important constituent of many Ayurvedic cough syrups and expectorants. It helps to mobilize mucus in bronchitis and asthma. Chewing tulsi leaves relieves cold and flu.

 Sore Throat: Water boiled with XXXXXXX leaves can be taken as drink in case of sore throat. This water can also be used as a gargle.

 Respiratory Disorder: The herb is useful in the treatment of respiratory system disorder. A decoction of the leaves, with honey and ginger is an effective remedy for bronchitis, asthma, influenza, cough and cold. A decoction of the leaves, cloves and common salt also gives immediate relief in case of influenza. They should be boiled in half a liter of water till only half the water is left and add then taken.
Thanks and best of luck.

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