For acute, uncomplicated cases, a synthetic penicillin is used most commonly amoxicillin (such as Amoxil, Polymox, or Trimox). This antibiotic is effective against the usual microorganisms and is relatively inexpensive. Amoxicillin's main side effects include allergic reactions (throat swelling, hives) and stomach upset.

People allergic to penicillin can take a sulfur-containing antibiotic called trimethoprim/sulfamethoxazole or TMP/SMX (such as Bactrim, Cotrim, or Septra). This drug is not recommended for people who are allergic to sulfur.

People who have several episodes of partially treated acute sinusitis or those who have chronic sinusitis may become resistant to amoxicillin and TMP/SMX. Newer synthetic penicillins and cephalosporins such as Augmentin, cefuroxime (Ceftin), and loracarbef (Lorabid) can clear most of the resistant organisms that cause sinus infection.

Overuse of these "broader-spectrum" antibiotics may eventually lead to organisms evolving that can resist even the most potent antibiotics currently available. Therefore, simpler antibiotics such as amoxicillin should be used first and taken for the entire duration (14-21 days). The basic rule of thumb is to take the antibiotic until the symptoms disappear, and then continue to take the antibiotic for one more week.

Home remedies that open and hydrate the sinuses may promote drainage. See Self-Care at Home for information on increasing daily fluid intake, inhaling steam, and taking expectorants and pain relievers.

If environmental allergies cause the sinusitis, an antihistamine may help reduce swelling of the mucous membranes. Allergens stimulate white blood cells in the blood and tissues to release histamine into the circulation. This causes fluid to leak from blood vessels into the tissues of the nasal passageways, leading to nasal congestion symptoms.

Some of the older sedating OTC antihistamines are no longer recommended because they tend to dry out and thicken the mucus, making drainage more difficult.

Non-sedating antihistamines such as fexofenadine (Allegra), loratadine (Claritin), or desloratadine (Clarinex) do not seem to dry out the mucosa. If nasal congestion is severe, a decongestant can be added (for example, Allegra-D or Claritin-D).

To treat acute sinusitis, one or more OTC or prescription therapies may be all that is necessary. For those with recurrent bouts of acute sinusitis or chronic sinusitis, the addition of an intranasal steroid may reduce symptoms. Commonly prescribed medications are beclomethasone (Beconase), fluticasone (Flonase), triamcinolone (Nasacort), flunisolide (Nasalide), and Vancenase. Steroids are potent inhibitors of inflammation.

Intranasal steroids (nasal sprays) work directly on the lining of the nasal passages and sinuses with little effect on the rest of the body when taken in prescribed dosages.

As with the other classes of drugs, many intranasal steroids are available. Some are more tolerable than others. These are prescription medications. These drugs do not relieve symptoms immediately like nasal and oral decongestants do, but once therapeutic drug levels are achieved, symptoms usually improve, and decongestants may be unnecessary.

During months when environmental allergens are most widespread, the early administration of intranasal steroids may help to prevent sinusitis and keep the sinuses open and draining.