Antibiotics for sinus infections, such as amoxicillin, doxycycline, or levofloxacin, can be prescribed by a doctor to treat cases of acute or chronic bacterial sinusitis. These help to eliminate bacteria to relieve inflammation in the sinuses.

Sinus infections causes by bacterial sinusitis are characterized by symptoms such as nasal congestion, green phlegm, fever, headache, pain around the eyes and a feeling of heaviness in the face. Learn more about the typical symptoms of a sinus infection.

Treatment with antibiotics should be carried out as prescribed by a doctor. Treatment time can vary from 5 to 14 days, depending on the severity of the infection and the response to treatment.

Main antibiotics

The most commonly prescribed antibiotics for sinus infections are:

1. Amoxicillin

Amoxicillin or amoxicillin + clavulanate is usually the first treatment option for bacterial sinusitis in people who are not allergic to penicillins. It is capable of eliminating the most common types of bacteria that cause bacterial sinusitis, such as Streptococcus pneumoniae and Haemophilus influenzae.

How to take: The usual recommended dose of amoxicillin for adults is 500 mg orally, 3 times a day, or 875 mg, 2 times a day, for 5 to 10 days.

In the case of amoxicillin + clavulanate, the recommended doses for adults or children over 12 years of age is one tablet of amoxicillin 500 mg + clavulanate 125 mg, every 8 hours, or 1 tablet of amoxicillin 875 mg + clavulanate 125 mg, every 12 hours, as advised by the doctor.

2. Clarithromycin

Clarithromycin is an antibiotic from the macrolide class. It is usually indicated as the first choice for people allergic to penicillins, as it is capable of eliminating bacteria such as Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis.

How to take: The recommended dose for adults is one tablet of 250 mg, or one tablet of 500 mg, every 12 hours, as prescribed by your doctor.

3. Cefuroxime axetil

Cefuroxime axetil is an antibiotic from the cephalosporin class. It is indicated to eliminate bacteria such as S. pneumoniae and H. influenzae, helping to relieve the symptoms of bacterial sinusitis.

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

4. Doxycycline

Doxycycline is an antibiotic of the tetracycline class which acts by interfering with the metabolism of bacteria such as Moraxella catarrhalis and Haemophilus influenzae. It prevents their proliferation, and may be indicated for people allergic to penicillins.

How to take: The recommended dose of doxycycline 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 is another antibiotic that can be used by people allergic to penicillins in cases of moderate to severe bacterial sinusitis. In some cases, it can be combined with another antibiotic, cefixime, to help eliminate resistant S. pneumoniae and H. influenzae bacteria.

How to take: the recommended dose of clindamycin for adults is 300 mg, 3 times a day, as advised by your doctor.

6. Moxifloxacin

Moxifloxacin is an antibiotic from the fluoroquinolone class, indicated for acute bacterial sinusitis. It inhibits enzymes in bacteria, preventing them from multiplying and inducing cellular death to relieve the symptoms of the infection.

How to take: The recommended dose for adults is one tablet of 400 mg, once a day, for 7 days of treatment, or as prescribed by your doctor. Moxifloxacin should not be used by children.

7. Levofloxacin

Levofloxacin is another antibiotic from the fluoroquinolone class, which can be used by people who are allergic to penicillins. It helps to eliminate the bacteria that cause acute bacterial sinusitis, such as Streptococcus pneumoniae, Haemophilus influenza and Moraxella catarrhalis.

However, both levofloxacin and moxifloxacin should only be used when other treatment options are not indicated, due to the increased risk of side effects.

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

8. Metronidazole

Metronidazole is an antibiotic that can be used together with other antibiotics, such as amoxicillin or clindamycin, for bacterial sinusitis in people who have catarrh with pus and a foul smell, or abscess formation, in order to increase coverage against anaerobic bacteria.

How to take: The recommended dose for adults is 500 mg, 3 times a day, as prescribed.

Side effects of antibiotics

The most common side effects that can arise during antibiotic treatment are:

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

In addition, antibiotics can cause serious allergic reactions or anaphylaxis, which require immediate medical attention.

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

When to use

Antibiotics for a sinus infection are indicated when it is suspected that the infection has been caused by bacteria. They should only be used under the monitoring of a doctor, who can indicate the most suitable antibiotic and the length of treatment.

When not to use

Antibiotics should not be used in cases of sinus infections caused by viruses or fungi, as these will only be effective against bacteria.

In addition, children, pregnant or breastfeeding women, or people who have kidney or liver problems or diseases should only take antibiotics if recommended after careful evaluation.

Other remedies for sinusitis

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

The doctor may recommend the use of painkillers, corticosteroids or nasal decongestants.

It's also important to irrigate your nose with saline solution, as this helps to thin out secretions and eliminate phlegm from the nose and sinuses.

Care during treatment

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

Take the antibiotic correctly in the doses and at the times set by the doctor
Do not interrupt treatment on your own
Take the treatment for the correct length of time determined by the doctor, even if symptoms improve a few days after starting the antibiotic
Consult the doctor again if symptoms do not improve after 3 to 4 days of treatment

Ask the doctor or pharmacist if the antibiotic can be taken before or after a meal, with water or milk, so as not to interfere with the effectiveness of the treatment.

It is important to follow all medical recommendations when using antibiotics in order to avoid bacterial resistance, which can make treating the infection more difficult and time-consuming, as well as causing symptoms to worsen.