Symptoms such as high fever, severe facial pain, swelling around the eyes, or worsening sinus pressure may indicate a bacterial sinus infection that requires medical evaluation.
Difficulty breathing, throat tightness, swelling of the face or tongue, hives, or blistering skin after taking antibiotics may signal a serious allergic reaction and require immediate medical attention.
Symptoms that do not improve or worsen after 3 to 4 days of antibiotic treatment should be evaluated by a doctor to rule out complications or the need for a different medication.

Antibiotics for sinus infections are used to treat bacterial sinusitis when symptoms such as nasal congestion, thick yellow or green mucus, facial pressure, headache, and fever develop. These medications help eliminate bacteria in the sinuses and reduce inflammation.

Common antibiotics for sinus infections include amoxicillin, amoxicillin-clavulanate, cefdinir, doxycycline, and other options that may be prescribed depending on the infection and medical history. Treatment typically lasts about 5 to 14 days and should always be taken as directed by a doctor.

Some antibiotics are used as first-line treatment, while others may be recommended when allergies or resistance are present. Antibiotics for sinus infections can also cause side effects and should only be used when the infection is caused by bacteria rather than viruses.

Main antibiotics

The most commonly prescribed antibiotics for sinus infections are:

1. Amoxicillin or amoxicillin + clavulanate

Amoxicillin, alone or combined with clavulanate, is usually the first treatment option for bacterial sinusitis in people who are not allergic to penicillins. The combination with clavulanate is commonly preferred because it is effective against the most common bacteria that cause sinus infections, such as Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

How to take: The usual recommended dose of amoxicillin for adults is 500 mg orally, 3 times a day, or 875 mg twice a day, for 5 to 10 days.

For amoxicillin + clavulanate, the recommended dose for adults or children over 12 years old is one tablet of amoxicillin 500 mg + clavulanate 125 mg every 8 hours, or one tablet of amoxicillin 875 mg + clavulanate 125 mg every 12 hours, as advised by the doctor.

2. Cefdinir

Cefdinir is an antibiotic from the cephalosporin class that helps eliminate bacteria such as Streptococcus pneumoniae and Haemophilus influenzae. It is often used as an alternative treatment option when amoxicillin cannot be used or when a different antibiotic is needed.

How to take: The recommended dose for adults is 300 mg every 12 hours or 600 mg once a day, as prescribed by the doctor.

3. Cefuroxime axetil

Cefuroxime axetil is another antibiotic from the cephalosporin class that can help eliminate bacteria such as Streptococcus pneumoniae and Haemophilus influenzae, relieving the symptoms of bacterial sinusitis.

How to take: The recommended dose for adults is one 250 mg tablet every 12 hours. For children aged 3 months to 12 years, an oral suspension is usually prescribed, with doses calculated by the pediatrician according to the child's body weight.

4. Doxycycline

Doxycycline is an antibiotic from the tetracycline class that works by interfering with bacterial metabolism. It prevents bacteria such as Moraxella catarrhalis and Haemophilus influenzae from multiplying and can be used as an alternative treatment for people who are allergic to penicillins.

How to take: The recommended dose for adults is 100 mg twice a day or 200 mg once a day, according to medical advice. For children over 8 years old, the dose should be calculated by the pediatrician according to the child’s weight.

5. Clindamycin

Clindamycin may be used by people who are allergic to penicillins in cases of moderate to severe bacterial sinusitis. In some cases, it can be combined with another antibiotic, such as cefixime, to help eliminate resistant bacteria like Streptococcus pneumoniae and Haemophilus influenzae.

How to take: The recommended dose for adults is 300 mg three times a day, as advised by the doctor.

6. Levofloxacin

Levofloxacin is an antibiotic from the fluoroquinolone class that helps eliminate bacteria responsible for acute bacterial sinusitis, such as Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

However, levofloxacin is generally reserved for situations in which other treatment options cannot be used, due to the increased risk of side effects.

How to take: The usual recommended dose for adults is 500 mg to 750 mg once a day for about 5 days, or as prescribed by the doctor.

7. Moxifloxacin

Moxifloxacin is another antibiotic from the fluoroquinolone class that may be used to treat acute bacterial sinusitis when other antibiotics are not appropriate or effective.

How to take: The recommended dose for adults is one 400 mg tablet once a day for about 7 days, or according to the doctor’s instructions. Moxifloxacin should not be used by children.

8. Metronidazole

Metronidazole may be used together with other antibiotics, such as amoxicillin or clindamycin, in cases of bacterial sinusitis with foul-smelling discharge, pus, or abscess formation. It helps increase coverage against anaerobic bacteria that may be present in more complicated infections.

How to take: The recommended dose for adults is 500 mg three times a day, as prescribed by the doctor.

Side effects of antibiotics

The most common side effects that can occur during antibiotic treatment include:

Stomach pain
Diarrhea
Nausea or vomiting
Poor digestion
Sensitivity to light
Lack of appetite
Blurred vision
Tooth discoloration
Ringing in the ears
Headache
Blood or mucus in the stool
Fungal infections
Altered functioning of the liver, kidneys or other organs

Antibiotics can also cause serious allergic reactions or anaphylaxis, which require immediate medical attention.

If symptoms such as difficulty breathing, a tight throat, swelling of the mouth, tongue or face, blistering of the skin, or hives occur, discontinue treatment immediately and seek urgent medical attention.

When to use

Antibiotics for sinus infections are indicated when it is suspected that the infection is caused by bacteria. They should only be used under the supervision of a doctor, who can recommend the most appropriate antibiotic and determine the length of treatment.

When not to use

Antibiotics should not be used for sinus infections caused by viruses or fungi, as they are only effective against bacteria.

In addition, children, pregnant or breastfeeding women, and people with kidney or liver problems should only take antibiotics after careful medical evaluation and recommendation.

Other remedies for sinusitis

In addition to antibiotics, sinus infections can be treated with other medications that help relieve symptoms and reduce inflammation.

A doctor may recommend pain relievers, corticosteroids, or nasal decongestants.

It is also important to irrigate the nose with saline solution, as this helps thin secretions and remove mucus from the nose and sinuses.

Care during treatment

When taking antibiotics for sinus infections, it is important to follow certain precautions:

Take the antibiotic exactly as prescribed by the doctor
Do not stop treatment on your own
Complete the full course of treatment even if symptoms improve
Contact the doctor if symptoms do not improve after 3 to 4 days
Ask the doctor or pharmacist whether the antibiotic should be taken with food, water, or milk to avoid interfering with treatment effectiveness

Following medical recommendations when using antibiotics is important to prevent bacterial resistance, which can make infections harder to treat and may worsen symptoms.

Antibiotics for Sinus Infections: Medication List & Treatment Guide