Recommended treatments for most cases of sinusitis include rest and drinking enough water to thin the mucus. Antibiotics are not recommended for most cases.

Breathing low-temperature steam such as from a hot shower or gargling can relieve symptoms. There is tentative evidence for nasal irrigation. Decongestant nasal sprays containing oxymetazoline may provide relief, but these medications should not be used for more than the recommended period. Longer use may cause rebound sinusitis. It is unclear if nasal irrigation, antihistamines, or decongestants work in children with acute sinusitis.

Most sinusitis cases are caused by viruses and resolve without antibiotics. However, if symptoms do not resolve within 10 days, amoxicillin is a reasonable antibiotic to use first for treatment with amoxicillin/clavulanate being indicated when the person's symptoms do not improve after 7 days on amoxicillin alone. A 2012 Cochrane review, however, found only a small benefit between 7 and 14 days, and could not recommend the practice when compared to potential complications and risk of developing resistance. Antibiotics are specifically not recommended in those with mild / moderate disease during the first week of infection due to risk of adverse effects, antibiotic resistance, and cost.

Fluoroquinolones, and a newer macrolide antibiotic such as clarithromycin or a tetracycline like doxycycline, are used in those who have severe allergies to penicillins. Because of increasing resistance to amoxicillin the 2012 guideline of the Infectious Diseases Society of America recommends amoxicillin-clavulanate as the initial treatment of choice for bacterial sinusitis. The guidelines also recommend against other commonly used antibiotics, including azithromycin, clarithromycin, and trimethoprim/sulfamethoxazole, because of growing antibiotic resistance. The FDA recommends against the use of fluoroquinolones when other options are available due to higher risks of serious side effects.

A short-course (3–7 days) of antibiotics seems to be just as effective as the typical longer-course (10–14 days) of antibiotics for those with clinically diagnosed acute bacterial sinusitis without any other severe disease or complicating factors. The IDSA guideline suggest five to seven days of antibiotics is long enough to treat a bacterial infection without encouraging resistance. The guidelines still recommend children receive antibiotic treatment for ten days to two weeks.

In cases of viral adenoiditis, treatment with analgesics or antipyretics is often sufficient. Bacterial adenoiditis may be treated with antibiotics, such as amoxicillin - clavulanic acid or a cephalosporin. In case of adenoid hypertrophy, adenoidectomy may be performed to remove the adenoid.

Reduction of hypertrophied turbinates, correction of nasal septum deviation, removal of polyps, sectioning of the parasympathetic secretomotor fiber to nose (vidian neurectomy) for controlling refractory excessive rhinorrhea.

Prescribing antibiotics for laryngitis is not suggested practice. The antibiotics penicillin V and erythromycin are not effective for treating acute laryngitis. Erythromycin may improve voice disturbances after one week and cough after two weeks, however any modest subjective benefit is not greater than the adverse effects, cost, and the risk of bacteria developing resistance to the antibiotics. Health authorities have been strongly encouraging physicians to decrease the prescribing of antibiotics to treat common upper respiratory tract infections because antibiotic usage does not significantly reduce recovery time for these viral illnesses. Decreased antibiotic usage could also have prevented drug resistant bacteria. Some have advocated a delayed antibiotic approach to treating URIs which seeks to reduce the consumption of antibiotics while attempting to maintain patient satisfaction. Most studies show no difference in improvement of symptoms between those treated with antibiotics right away and those with delayed prescriptions. Most studies also show no difference in patient satisfaction, patient complications, symptoms between delayed and no antibiotics. A strategy of "no antibiotics" results in even less antibiotic use than a strategy of "delayed antibiotics".

The avoidance of inciting factors such as sudden changes in temperature, humidity, or blasts of air or dust is helpful.

Intranasal application of antihistamines, corticosteroids, or anticholinergics may also be used for vasomotor rhinitis. Intranasal cromolyn sodium may be used in patients older than two years.

Astelin (Azelastine) "is indicated for symptomatic treatment of vasomotor rhinitis including rhinorrhea, nasal congestion, and post nasal drip in adults and children 12 years of age and older."

In most cases treatment for rhinorrhea is not necessary since it will clear up on its own—especially if it is the symptom of an infection. For general cases blowing your nose can get rid of the mucus buildup. Though blowing may be a quick-fix solution, it would likely proliferate mucosal production in the sinuses, leading to frequent and higher mucus buildups in the nose. Alternatively, saline nasal sprays and vasoconstrictor nasal sprays may also be used, but may become counterproductive after several days of use, causing rhinitis medicamentosa.

In recurring cases, such as those due to allergies, there are medicinal treatments available. For cases caused by histamine buildup, several types of antihistamines can be obtained relatively cheaply from drugstores.

People who prefer to keep clear nasal passages, such as singers, who need a clear nasal passage to perform, may use a technique called "nasal irrigation" to prevent rhinorrhea. Nasal irrigation involves rinsing the nasal cavity regularly with salty water or store bought saline solutions.

The Centers for Disease Control describe protocol for treating sinusitis while at the same time discouraging overuse of antibiotics:

- Target likely organisms with first-line drugs: Amoxicillin, Amoxicillin/Clavulanate

- Use shortest effective course: Should see improvement in 2–3 days. Continue treatment for 7 days after symptoms improve or resolve (usually a 10–14 day course).

- Consider imaging studies in recurrent or unclear cases: some sinus involvement is frequent early in the course of uncomplicated viral URI

Treatment comprises symptomatic support usually via analgesics for headache, sore throat and muscle aches. Moderate exercise in sedentary subjects with naturally acquired URTI probably does not alter the overall severity and duration of the illness. No randomized trials have been conducted to ascertain benefits of increasing fluid intake.

Treatment for fungal sinusitis can include surgical debridement; helps by slowing progression of disease thus allowing time for recovery additionally we see the options below:

- In the case of invasive fungal sinusitis, echinocandins, voriconazole, and amphoterecin (via IV) may be used

- For allergic fungal sinusitis, systemic corticosteroids like prednisolone, methylprednisolone are added for their anti-inflammatory effect, bronchodilators and expectorants help to clear secretions in the sinuses.

First-generation antihistamine has been suggested as first-line therapy to treat post-nasal drip.

Treatment of atrophic rhinitis can be either medical or surgical.

Medical measures include:

- Nasal irrigation using normal saline

- Nasal irrigation and removal of crusts using alkaline nasal solutions prepared by dissolving a spoonful of powder containing one part sodium bicarbonate, one part sodium biborate and two part sodium chloride.

- 25% glucose in glycerine can be applied to the nasal mucosa to inhibit the growth of proteolytic organisms which produce foul smell.

- Local antibiotics, such as chloromycetine.

- Vitamin D (Kemicetine).

- Estradiol spray for regeneration of seromucinous glands and vascularization of mucosa.

- Systemic streptomycin (1g/day) against Klebsiella organisms.

- Oral potassium iodide for liquefaction of secretion.

- Placental extract injected in the submucosa.

Surgical interventions include:

- Young's operation.

- Modified Young's operation.

- Narrowing of nasal cavities, submucosal injection of Teflon paste, section and medial displacement of the lateral wall of the nose.

- Transposition of parotid duct to maxillary sinus or nasal mucosa.

Although orbital cellulitis is considered an ophthalmic emergency the prognosis is good if prompt medical treatment is received.

Immediate treatment is very important for someone with orbital cellulitis. Treatment typically involves intravenous (IV) antibiotics in the hospital and frequent observation (every 4–6 hours). Along with this several laboratory tests are run including a complete blood count, differential, and blood culture.

- Antibiotic therapy – Since orbital cellulitis is commonly caused by "Staphylococcus" and "Streptococcus" species both penicillins and cephalosporins are typically the best choices for IV antibiotics. However, due to the increasing rise of MRSA (methicillin-resistant "Staphylococcus aureus") orbital cellulitis can also be treated with Vancomycin, Clindamycin, or Doxycycline. If improvement is noted after 48 hours of IV antibiotics, healthcare professions can then consider switching a patient to oral antibiotics (which must be used for 2–3 weeks).

- Surgical intervention – An abscess can threaten the vision or neurological status of a patient with orbital cellulitis, therefore sometimes surgical intervention is necessary. Surgery typically requires drainage of the sinuses and if a subperiosteal abscess is present in the medial orbit, drainage can be performed endoscopically. Post-operatively, patients must follow up regularly with their surgeon and remain under close observation.

The first line of treatment for nasal polyps is topical steroids. Steroids decrease the inflammation of the sinus mucosa to decrease the size of the polyps and improve symptoms. Topical preparations are preferred in the form of a nasal spray, but are often ineffective for people with many polyps. Steroids by mouth often provide drastic symptom relief, but should not be taken for long periods of time due to their side effects. Because steroids only shrink the size and swelling of the polyp, people often have recurrence of symptoms once the steroids are stopped. Decongestants do not shrink the polyps, but can decrease swelling and provide some relief. Antibiotics are only recommended if the person has a co-occurring bacterial infection.

In people with nasal polyps caused by aspirin or NSAIDs, avoidance of these medications will help with symptoms. Aspirin desensitization has also been shown to be beneficial.

Antibiotics are commonly used to prevent secondary bacterial infection. There are no specific antiviral drugs in common use at this time for FVR, although one study has shown that ganciclovir, PMEDAP, and cidofovir hold promise for treatment. More recent research has indicated that systemic famciclovir is effective at treating this infection in cats without the side effects reported with other anti-viral agents. More severe cases may require supportive care such as intravenous fluid therapy, oxygen therapy, or even a feeding tube. Conjunctivitis and corneal ulcers are treated with topical antibiotics for secondary bacterial infection.

Lysine is commonly used as a treatment, however in a 2015 systematic review, where the authors investigated all clinical trials with cats as well as "in vitro" studies, concluded that lysine supplementation is not effective for the treatment or prevention of feline herpesvirus 1 infection.

The preferred treatment for many patients is desensitization to aspirin, undertaken at a clinic or hospital specializing in such treatment. In the United States, the Scripps Clinic in San Diego, CA, the Massachusetts General Hospital in Boston, MA, the Brigham and Women's Hospital in Boston, MA, National Jewish Hospital in Denver and Stanford University Adult ENT Clinic have allergists who routinely perform aspirin desensitization procedures for patients with aspirin-induced asthma. Patients who are desensitized then take a maintenance dose of aspirin daily and while on daily aspirin they often have reduced need for supporting medications, fewer asthma and sinusitis symptoms than previously, and many have an improved sense of smell. Desensitization to aspirin reduces the chance of nasal polyp recurrence, and can slow the regrowth of nasal polyps. Even patients desensitized to aspirin may continue to need other medications including nasal steroids, inhaled steroids, and leukotriene antagonists.

Leukotriene antagonists and inhibitors (montelukast, zafirlukast, and zileuton) are often helpful in treating the symptoms of aspirin-induced asthma. Some patients require oral steroids to alleviate asthma and congestion, and most patients will have recurring or chronic sinusitis due to the nasal inflammation.

Adenoiditis occurs mainly in childhood, often associated with acute tonsillitis. Incidence decreases with age, with adenoiditis being rare in children over 15 years due to physiological atrophy of the adenoid tissue.

Often surgery is required to remove nasal polyps, although they typically recur, particularly if aspirin desensitization is not undertaken. 90% of patients have been shown to have recurrence of nasal polyps within 5 years after surgery, with 47% requiring revision surgery in the same time period.

Endoscopic sinus surgery with removal of polyps is often very effective for most people providing rapid symptom relief. Endoscopic sinus surgery is minimally-invasive and is done entirely through the nostril with the help of a camera. Surgery should be considered for those with complete nasal obstruction, uncontrolled runny nose, nasal deformity caused by polyps or continued symptoms despite medical management. Surgery serves to remove the polyps as well as the surrounding inflamed mucosa, open obstructed nasal passages, and clear the sinuses. This not only removes the obstruction caused by the polyps themselves, but allows medications such as saline irrigations and topical steroids to become more effective.

Surgery lasts approximately 45 minutes to 1 hour and can be done under general or local anesthesia. Most patients tolerate the surgery without much pain, though this can vary from patient to patient. The patient should expect some discomfort, congestion, and drainage from the nose in the first few days after surgery, but this should be mild. Complications from endoscopic sinus surgery are rare, but can include bleeding and damage to other structures in the area including the eye or brain.

Many physicians recommend a course of oral steroids prior to surgery to reduce mucosal inflammation, decrease bleeding during surgery, and help with visualization of the polyps. Nasal steroid sprays should be used preventatively after surgery to delay or prevent recurrence. People often have recurrence of polyps even following surgery. Therefore, continued follow up with a combination of medical and surgical management is preferred for the treatment of nasal polyps.

Medications may be needed as an adjunct to assist the closure of the defect. Antibiotics can help control or prevent any sinus infections. Preoperative nasal decongestants usage can reduce any existing sinus inflammation which will aid surgical manipulation of the mucosa over the bone.

Broad-spectrum intravenous antibiotics are used until a definite pathogen is found.

1. Nafcillin 1.5 g IV q4h

2. Cefotaxime 1.5 to 2 g IV q4h

3. Metronidazole 15 mg/kg load followed by 7.5 mg/kg IV q6h

Vancomycin may be substituted for nafcillin if significant concern exists for infection by methicillin-resistant "Staphylococcus aureus" or resistant "Streptococcus pneumoniae". Appropriate therapy should take into account the primary source of infection as well as possible associated complications such as brain abscess, meningitis, or subdural empyema.

All people with CST are usually treated with prolonged courses (3–4 weeks) of IV antibiotics. If there is evidence of complications such as intracranial suppuration, 6–8 weeks of total therapy may be warranted.

All patients should be monitored for signs of complicated infection, continued sepsis, or septic emboli while antibiotic therapy is being administered.

Antibiotics are aimed at gram positive bacteria. Medical attention should be sought if symptoms persist beyond 2–3 days.

Anticoagulation with heparin is controversial. Retrospective studies show conflicting data. This decision should be made with subspecialty consultation. One systematic review concluded that anticoagulation treatment appeared safe and was associated with a potentially important reduction in the risk of death or dependency.

There is a vaccine for FHV-1 available (ATCvet code: , plus various combination vaccines), but although it limits or weakens the severity of the disease and may reduce viral shedding, it does not prevent infection with FVR. Studies have shown a duration of immunity of this vaccine to be at least three years. The use of serology to demonstrate circulating antibodies to FHV-1 has been shown to have a positive predictive value for indicating protection from this disease.

Normal surgical masks and N95 masks appear equivalent with respect to preventing respiratory infections.