What are antibiotics?

Antibiotics are a type of antimicrobial drug used to treat bacterial infections. Doctors use these drugs in the treatment of humans and animals. A course of antibiotic treatment will kill bacteria in the body, which will treat the infection while preventing the invasive microbes from spreading.

Your body has natural defenses against bacteria–namely, “good bacteria” (e.g., lactobacillus) and white blood cells. Bacterial infections occur when harmful bacteria overpopulate or overtake these natural defense systems. Antibiotic drugs supplement your body’s natural immune system response by targeting these microbes.

Antibiotics are supplied in several forms. They can be prescribed as an oral tablet, capsule or liquid. They can be used topically as a medicated gel or cream or administered via intravenous injection.

It should be noted that antibiotics are only used to treat bacterial infections. They are ineffective against viral infections (like the common cold or bronchitis), fungal infections or any other type of infection. The overuse of antibiotics can cause serious side effects and antibiotic resistance.

What are antibiotics used to treat?

A prescribing clinician will order the use of antibiotics for bacterial infections. Common types of bacteria that cause infection include Escherichia coli (E. coli), Staphylococcus and Streptococcus.

Common types of bacterial infection include:

Strep throat: Strep throat is a bacterial infection caused by a bacteria known as Group A streptococcus. Strep throat is highly contagious, especially among children. Common symptoms of strep throat include sore throat, fever and body aches.

Urinary tract infections: Urinary tract infection (UTI) is a common infection of the urinary tract. They usually occur when bacteria enter the urethra (the tube that carries urine out of the bladder). The bladder and urethra are the most commonly affected parts of the urinary tract. However, a UTI can affect any component of the urinary system, including the kidneys, ureters, bladder, and urethra. Common symptoms include a strong urge to urinate, pain during urination and abdomen pain.

Ear infections: An ear infection - also known as otitis media - is an infection of the middle ear. The middle ear is an air-filled cavity behind the eardrum and transmits sound from the outer ear to the inner ear. Symptoms include ear pain and fever.

Skin infections: Skin infections occur when a pathogen - an organism that causes disease - affects the skin. Bacteria, viruses, fungi, or parasites may cause skin infections. Common types of bacterial skin infections include cellulitis (a potentially life-threatening infection caused by the Staphylococcus and Streptococcus bacteria), Methicillin-resistant Staphylococcus Aureus (MRSA), impetigo (a mild infection that usually affects children under 12), and boils (bacterial infections of the hair follicles).

STIs: Certain types of sexually transmitted infections like chlamydia and gonorrhea are caused by invasive bacteria. Common symptoms of these infections include pain during urination and abnormal discharge from the genitals. Serious infections: Serious bacterial infections like sepsis and meningitis may require an intravenous antibiotic injection. A health care professional performs antibiotic injections at a medical facility.

Antibiotics are not used for the treatment of viral infections or fungal infections. A viral infection is treated with antiviral drugs or a vaccine, while fungal infections require antifungal treatment. Antibacterial drugs will not be prescribed for the flu, most coughs or sinus infections.

What are the different types of antibiotics?

Different types of antibiotics are grouped by their chemical makeup. The primary classes of antibiotics are listed below, along with specific drugs in that class.

• Penicillins: Amoxicillin and Ampicillin
  
• Tetracyclines: Minocycline
  
• Cephalosporins: Cephalexin and Cefdinir
  
• Macrolides: Azithromycin and Erythromycin
  
• Fluoroquinolones: Ciprofloxacin and Levofloxacin
  
• Aminoglycosides: Tobramycin
  
• Lincosamides: Clindamycin
  
  

Some antibiotics work on a wide range of bacteria. These specific drugs are known as broad-spectrum antibiotics. Narrow-spectrum antibiotics like lincosamides are prescribed to patients who have a penicillin allergy or are experiencing infections that may recur.

What are the common side effects of antibiotics?

Antibiotic drugs have different chemical makeups, meaning that the side effects may vary.

Common adverse reactions include:

• Skin rash
  
• Nausea
  
• Vomiting
  
• Diarrhea - up to 30% of the time
  
• Dizziness
  
  

Supplementing your diet with yogurt or pro-biotics is the best way to prevent diarrhea while taking antibiotics.

If you begin to experience a skin rash, hives or difficulty breathing after taking an antibiotic, you should seek medical attention immediately. These are early signs of an allergic reaction–a potentially life-threatening medical emergency.

Before starting treatment with any antibiotic, talk to your health care provider about any medications or supplements you are taking. Antibiotics can interact with other drugs and substances, potentially causing adverse reactions. You should also tell your provider if you are pregnant or plan to become pregnant before starting antibiotic treatment.

In addition to the side effects listed above, antibiotics carry the risk of contributing to antimicrobial resistance.

What is antimicrobial resistance?

The overuse of antibiotics, or the use of antibiotics when they aren’t necessary, can lead to harmful bacteria becoming resistant to these drugs. Antibiotic-resistant bacteria no longer respond to certain types of medication, and antibiotic-resistant infections become significantly harder to treat.

Antimicrobial resistance is a public health concern that jeopardizes people’s ability to fight and prevent infection. According to the Centers for Disease Control and Prevention (CDC), nearly 30% of antibiotic courses are incorrectly prescribed. This means that the underlying illness did not require antibiotic treatment.

To prevent antimicrobial resistance, take your medication exactly as your health care provider prescribes. Take the entire course of antibiotic treatment, and do not take antibiotics prescribed to someone else. Talk to your health care provider if you have any questions about your treatment.

Do I need a prescription for antibiotics?

In most cases, yes. While some over-the-counter antibacterial medicines are available for purchase, most antibiotic drugs require a prescription before you can use them. For more information about OTC antibiotics, check out our recent article.

Providers on Sesame can write a prescription – or refill an existing one – during a virtual or in-person visit. Depending on the medication, you can arrange for same-day pickup at a pharmacy near you. Book an online consultation with a real, licensed provider on Sesame today to determine whether or not antibiotics are right for you.

Looking for more information? If you’re experiencing the symptoms of illness or an infectious disease, you should book a video doctor visit with a licensed health care provider on Sesame to discuss your symptoms and possible treatment options.

Sources:

• Antimicrobial Resistance. Centers for Disease Control and Prevention. (2022). https://www.cdc.gov
  
• Antibiotic Use Q&As. Centers for Disease Control and Prevention. (2021). https://www.cdc.gov.
  
• Antimicrobial Resistance. NIH. (2023). https://www.niaid.nih.gov.
  
• Antibiotics. Chara Calhoun; Harrison R. Wermuth; Gregory A. Hall. (2022). https://www.ncbi.nlm.nih.gov
  
• Antibiotic Resistance. Yacob Habboush; Nilmarie Guzman. (2022). https://www.ncbi.nlm.nih.gov.
  
• Action and Resistance Mechanisms of Antibiotics. Garima Kapoor, Saurabh Saigal, and Ashok Elongavan. (2017). https://www.ncbi.nlm.nih.gov.
  

Sesame content is not intended to be a substitute for professional medical advice, diagnosis or treatment. If you have a medical concern, it is critical to seek the advice of your physician or another qualified health provider with any questions. If you are facing a medical emergency, call 911 or visit the nearest emergency room immediately.

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