Reasons to Take Them, Associated Risks & What to Expect

6 Reasons You Would Need Antibiotics

1. Sinus Infection

Also known as sinusitis, a sinus infection is inflammation or swelling of the tissue that lines the sinuses. Sinuses that fill with fluid and become blocked can cause bacteria to accumulate and develop an infection. Stuffy or runny nose, cough, congestion, and loss of smell are common symptoms of most sinus infections.[2]

Antibiotics can treat severe or long-lasting sinus infections, as these infections are bacterial. Many sinus infections tend to clear on their own within 10 days; a doctor might prescribe antibiotics if symptoms persist after the 10th day.[3]

2. Ear Pain or Infection

An ear infection is a bacterial or viral infection that affects the section of your middle ear behind the eardrum to cause inflammation and fluid buildup. Ear infections can result in severe ear pain and are commonly caused by colds, allergies, changes in air pressure, swollen adenoids, and sinus infections. Symptoms of ear infections include hearing loss, persistent pressure in the ear, pus-like ear drainage, and ear pain.[4]

Because ear infections can be either bacterial or viral, a doctor’s exam is necessary to determine the root cause of the ear pain and the infection. Antibiotics can treat ear infections diagnosed as bacterial.

3. Strep Throat

Strep throat is a bacterial infection characterized by inflammation and feelings of soreness, scratchiness, and pain in the throat. The Streptococcal bacteria that cause strep throat are highly contagious and can spread by sharing food and drinks with an infected person or by being near an infected person who is coughing and sneezing. Strep throat can also be contracted by touching Strep bacteria that resides on surfaces such as doorknobs, handles, and railings.[5]

Many strep infections tend to clear on their own, but severe cases can progress to more serious medical conditions, including rheumatic fever, pneumonia, sepsis, and shock. Doctors might prescribe antibiotics to treat Strep infections that don’t clear on their own or that become severe after testing to confirm that throat soreness is the result of Strep bacteria.

4. Conjunctivitis

Also known as pink eye, conjunctivitis is inflammation of the inner eyelid and outer membrane of the eye, or white of the eye. Pink eye can be caused by viruses such as the common cold, eye irritants that include dust and pollen, and bacteria. Common symptoms of pink eye include itching, watering of the eye, burning, sensitivity to light, and a pink appearance.[6]

The cause of conjunctivitis could be bacterial if it occurs shortly after or at the same time as an ear infection.[7] Bacterial conjunctivitis can also produce sticky yellow or greenish discharge at the corner of the eye and cause eyelids to stick together during sleep. Antibiotics treat cases of conjunctivitis diagnosed as bacterial.

5. Lyme Disease

Lyme disease is an infection caused by a bacterium called Borrelia burgdorferi that is transmitted to humans through a bite from an infected tick. People who spend time in grassy and heavily wooded areas are more likely to become infected by Lyme disease.[8] Common symptoms of Lyme disease include rash, flu-like symptoms, joint pain, meningitis, Bell’s palsy, problems with motor function, and other neurological issues.

Antibiotics are often the first line of treatment for Lyme disease. They can prevent Borrelia burgdorferi from taking over the immune system and staying in the body for long periods of time. Those who treat Lyme disease in its early stages using antibiotics tend to recover completely and relatively quickly from this bacterial infection.

6. Urinary Tract Infection

A urinary tract infection, or UTI, is any infection in the bladder, urethra, or kidneys. It occurs when bacteria enter the urinary tract through the urethra and multiply in the bladder. UTIs can be caused by the presence of bacteria called Escherichia coli in the gastrointestinal tract or when gastrointestinal bacteria spread from the anus to the urethra, sometimes during sexual activity.[9] Common symptoms of UTIs include urine that is red, pink, or cloudy; a strong urge to urinate; and a burning sensation when urinating.

UTIs are bacterial infections that can be safely and effectively treated using antibiotics. Symptoms generally clear within a few days of using antibiotics, but treatment could last longer than a week in severe cases.

Understanding Antibiotics

Antibiotics are medicines that target and kill bacterial cells to treat bacterial infections. Antibiotics only have the ability to kill bacteria and cannot kill viruses or treat viral infections. Different types of antibiotics kill bacteria in their own unique ways. For instance, penicillin is a beta-lactam antibiotic that kills bacteria surrounded by a cell wall. Erythromycin is a macrolide antibiotic that blocks bacteria cells responsible for building protein.[1]

Antibiotics are an evidence-based treatment for life-threatening bacterial infections, and they help prevent bacteria from infecting patients during surgery and other medical procedures. These drugs have been widely used since the 1940s to reduce rates of illness and death related to bacterial infections.[10]

Risks of Antibiotics

Overuse or misuse of antibiotics can lead to antibiotic resistance, which means antibiotics can stop working to kill bacterial infections. People who become resistant to antibiotics tend to develop more serious illnesses, experience longer recovery and hospitalization times, and might visit the doctor more frequently than those who are not resistant to these drugs.[11]

Using antibiotics when no bacterial infection is present could cause these medicines to attack good, “friendly” bacteria that are beneficial to health and do not contribute to disease. Losing friendly bacteria can allow for the multiplication of harmful bacteria that increase the risk for illness, disease, and infection.[1]

What to Expect With Antibiotics

Antibiotics tend to work relatively quickly and might relieve symptoms within a few days, but taking the full prescribed course of the medicine as directed helps ensure the bacterial infection is fully treated.

Antibiotics can cause a number of side effects, including nausea, vomiting, dizziness, abdominal pain, bloating, diarrhea, yeast infections, and loss of appetite. In some people, antibiotics cause additional side effects: hives, difficulty breathing, coughing, and wheezing.

Serious side effects of antibiotics include severe and life-threatening allergic reactions and an infection caused by bacteria called Clostridium difficile that inflame the colon and trigger severe diarrhea. In some instances, a Clostridium difficile infection might lead to colon damage and death.[12]

Questions to Ask Your Doctor About Antibiotics

  • What are the risks of using antibiotics?
  • Do I really need antibiotics to treat my health condition?
  • How do you know I can benefit from using antibiotics?
  • How can I use antibiotics safely?
  • What are the side effects of antibiotics?
  • How long do I need to take antibiotics?

Antibiotics May Also Be Known as

  • Antibacterials
  • Antimicrobials
  • Penicillin
  • Tetracycline
  • Beta-lactam[1]
  • Macrolides
  • Quinolones


  1. Learn Genetics. What is an Antibiotic?
  2. National Library of Medicine. Sinusitis.
  3. Brown University. Sinusitis: Patient Education Series.
  4. Harvard Health Publishing. Middle-Ear Infection (Otitis Media).
  5. National Library of Medicine. Strep Throat.
  6. Centers for Disease Control and Prevention. Conjunctivitis (Pink Eye) Symptoms.
  7. Centers for Disease Control and Prevention. Conjunctivitis (Pink Eye) Diagnosis.
  8. Centers for Disease Control and Prevention. Lyme Disease: What You Need to Know.
  9. National Library of Medicine. Urinary tract infections: epidemiology, mechanisms of infection and treatment options.
  10. Centers for Disease Control and Prevention. Antibiotic / Antimicrobial Resistance.
  11. Centers for Disease Control and Prevention. Antibiotic / Antimicrobial Resistance: About Antimicrobial Resistance.
  12. Centers for Disease Control and Prevention. Be Antibiotics Aware: Smart Use, Best Care.

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