Hi, welcome to healthcare magic
Rhinitis usually refer to symptoms related to the nose such as nasal discharge,
nasal congestion,
post nasal drip, sneezing
In
sinusitis a person may experience
facial pain, post nasal drip, headache,cough, fever,nasal discharge. Most persons have rhinitis and sinusitis combined.
Acute infections are those that last less than 4 weeks, if it lasts longer than that then it is called chronic.
Treatment would involve: avoiding any allergens that provoke the symptoms, use of antihistamines, use of an decongestant to releive the nasal congestion and runny nose, nasal sprays which also reduce the inflammation. In some persons if bacterial infection is suspected a short course of antibiotics may be required.
The antihistamines, nasal sprays and decongestants may be available over the counter in some areas but the antibiotics will require that you see a doctor for a prescription.
I hope this helps