- Bacterial Infections 101 Pictures Slideshow
- Take the Tummy Trouble Quiz
- Hepatitis C Slideshow Pictures
- Amoxicillin (Moxatag) vs. azithromycin (Zithromax): What's the difference?
- What is amoxicillin? What is azithromycin?
- What are the side effects of amoxicillin and azithromycin?
- What is the dosage for amoxicillin and azithromycin?
- What drugs interact with amoxicillin and azithromycin?
- Are amoxicillin and azithromycin safe to use while pregnant or breastfeeding?
Amoxicillin (Moxatag) vs. azithromycin (Zithromax): What's the difference?
- Amoxicillin and azithromycin are antibiotics used to treat bacterial infections of the middle ear, tonsils, throat, larynx (laryngitis), bronchi (bronchitis), lungs (pneumonia), urinary tract, skin, and some sexually transmitted diseases.
- Amoxicillin and azithromycin are different types of antibiotics. Amoxicillin is a penicillin-type antibiotic and azithromycin is a macrolide antibiotic.
- Brand names of amoxicillin include Moxatag and Amoxil.
- Brand names of azithromycin include Zithromax, Zithromax Tri-Pak, Zithromax Z-Pak, and Zmax.
- Side effects of amoxicillin and azithromycin that are similar include diarrhea, abdominal pain, nausea, vomiting, heartburn/indigestion, and rash.
- Side effects of amoxicillin that are different from azithromycin include dizziness, sleep problems (insomnia), itching, confusion, easy bruising, bleeding, and allergic reactions.
- Side effects of azithromycin that are different from amoxicillin include nervousness, vaginitis, tongue discoloration, and ringing in the ears.
What is amoxicillin? What is azithromycin?
Amoxicillin is a penicillin-type antibiotic, in the same class as ampicillin (Unasyn), piperacillin (Pipracil), and ticarcillin (Ticar). Penicillin-type antibiotics do not directly kill bacteria, but they stop bacteria from multiplying by preventing them from forming the walls that surround them. Bacterial walls protect bacteria from their environment and keep the contents of the bacterial cell together. Bacteria are unable to survive without a cell wall. Amoxicillin is effective against several different bacteria such as H. influenzae, N. gonorrhoea, E. coli, Streptococci, Pneumococci, and some strains of Staphylococci. Amoxicillin is used to treat bacterial infections of the middle ear, throat, tonsils, larynx (laryngitis), lungs (pneumonia), bronchi (bronchitis), urinary tract, and skin. It also is used to treat gonorrhea.
Azithromycin is a macrolide antibiotic chemically related to erythromycin and clarithromycin (Biaxin) used to treat otitis media (infection of the middle ear), tonsillitis, laryngitis, bronchitis, pneumonia, sinusitis, uncomplicated skin and skin structure infections, Mycobacterium avium complex, acute bacterial flare ups of chronic obstructive pulmonary disease (COPD), acute pelvic inflammatory disease, and several sexually transmitted infectious diseases (STDs) such as nongonococcal urethritis and cervicitis. It is effective against a wide variety of bacteria such as Hemophilus influenzae, Streptococcus pneumoniae, Mycoplasma pneumoniae, Staphylococcus aureus, mycobacterium avium, and many others.
What are the side effects of amoxicillin and azithromycin?
Side effects due to amoxicillin include
- abdominal pain,
- easy bruising,
- rash, and
- allergic reactions.
People who are allergic to the cephalosporin class of antibiotics, which are related to the penicillins, for example, cefaclor (Ceclor), cephalexin (Keflex), and cefprozil (Cefzil), may or may not be allergic to penicillins.
Serious but rare reactions include:
- severe allergic reactions (anaphylaxis), and
- low platelet (thrombocytopenia) or red blood cell count.
Amoxicillin can alter the normal bacteria in the colon and encourage overgrowth of some bacteria such as Clostridium difficile which causes inflammation of the colon (pseudomembranous colitis). Patients who develop signs of pseudomembranous colitis after starting amoxicillin (diarrhea, fever, abdominal pain, and possibly shock) should contact their physician immediately.
The most common side effects of azithromycin are:
- Diarrhea or loose stools
- Abdominal pain
Other possible side effects of azithromycin include:
- Tongue discoloration
- Ringing in the ears
Possible serious side effects of azithromycin include:
- Abnormal liver tests
- Cholestatic jaundice
- Steven-Johnson Syndrome
- Serious allergic reactions
- Abnormal heart beats
Antibiotics can alter the normal bacteria in the colon and encourage overgrowth of some bacteria such as Clostridium difficile, which causes inflammation of the colon (pseudomembranous colitis). Patients who develop signs of pseudomembranous colitis after starting azithromycin (diarrhea, fever, abdominal pain, and possibly shock) should contact their physician immediately.
Latest MedicineNet News
What is the dosage for amoxicillin and azithromycin?
- For most infections in adults the dose of amoxicillin is 250 mg every 8 hours, 500 mg every 8 hours, 500 mg every 12 hours or 875 mg every 12 hours, depending on the type and severity of infection.
- For the treatment of adults with gonorrhea, the dose is 3 g given as one dose.
- For most infections, children older than 3 months but less than 40 kg are treated with 25 or 45 mg/kg/day in divided doses every 12 hours or 20 or 40 mg/kg/day with one-third of the daily dose given every 8 hours depending on the type and severity of the infection.
- Amoxicillin can be taken with or without food.
- Azithromycin (except Zmax) can be taken with or without food, but food reduces stomach upset.
- Zmax should be taken on an empty stomach 1 hour before or 2 hours after a meal since food reduces its absorption.
- The adult azithromycin dose is 500-2000 mg in multiple or single doses.
- For most infections, azithromycin is taken once daily for a relatively short course of treatment (usually five days).
- The first dose is often a "double dose," twice as much as the remainder of the doses given.
- For acute bacterial sinusitis, azithromycin way be taken once daily for three days.
- Zmax usually is given as a single 2 gm dose.
What drugs interact with amoxicillin and azithromycin?
Amoxicillin is rarely associated with important drug interactions.
Azithromycin (except Zmax) should not be taken at the same time as aluminum- or magnesium-based antacids, such as Mylanta or Maalox, because antacids will bind the azithromycin and prevent it from being absorbed from the intestine.
Are amoxicillin and azithromycin safe to use while pregnant or breastfeeding?
- Penicillins are generally considered safe for use by pregnant women who are not allergic to penicillin.
- Small amounts of amoxicillin may be excreted in breast milk and may cause diarrhea or allergic responses in nursing infants. Amoxicillin is generally considered safe to use while breastfeeding. Amoxicillin is used to treat infections in the newborn.
- There are no adequate studies of azithromycin in pregnant women. Azithromycin should only be used during pregnancy if it is clearly necessary.
- It is not known if azithromycin is secreted in breast milk.
Subscribe to MedicineNet's General Health Newsletter
Amoxicillin (Moxatag) vs. azithromycin (Zithromax) are antibiotics used to treat bacterial infections of the middle ear, tonsils, throat, larynx (laryngitis), bronchi (bronchitis), lungs (pneumonia), urinary tract, skin, and some sexually transmitted diseases. Amoxicillin and azithromycin are different types of antibiotics. Amoxicillin is a penicillin-type antibiotic and azithromycin is a macrolide antibiotic.
Multimedia: Slideshows, Images & Quizzes
Bladder Infections: UTI Causes, Symptoms, Treatments
Urinary tract infections (UTI), including bladder infections, affect women and men, causing UTI symptoms like kidney infection....
Bacterial Infections 101: Types, Symptoms, and Treatments
Learn more about bacteria and the most common bacterial infections. Get more information on bacterial skin infections, which...
Ear Infection Quiz: Test Your Medical IQ
Is it possible to prevent ear infections? Take the Ear Infection (Otitis Media) Quiz to learn the risks, causes, symptoms and...
Related Disease Conditions
Bacterial vaginosis is an abnormal vaginal condition with signs and symptoms of vaginal discharge, vaginal odor, and vaginal...
H. pylori (Helicobacter Pylori) Infection
Helicobacter pylori (H. pylori) is a bacteria that causes chronic inflammation (gastritis) of the inner lining of the stomach,...
Ear Infection Home Treatment
Infections of the outer, middle, and inner ear usually are caused by viruses. Most outer (swimmer's ear) and middle ear...
SIBO (Small Intestinal Bacterial Overgrowth)
Small intestinal bacterial overgrowth (SIBO) refers to a condition in which abnormally large numbers of bacteria (at least...
CRE Infection (Carbapenem-Resistant Enterobacteriaceae)
Carbapenem-resistant Enterobacteriaceae (CRE) is a type of bacteria that is highly resistant to antibiotics. Escherichia coli (E....
Mycobacterium marinum (M. marinum) is bacteria found in fresh and saltwater that can infect the skin through cuts or scrapes,...
Nontuberculous Mycobacterial Lung Disease (NTM, Symptoms, Treatment, Side Effects)
Nontuberculous mycobacteria (NTM), most commonly, M. avium complex or MAC, is a mycobacteria that causes lung infections and...
Treatment & Diagnosis
- Ear Infection FAQs
- Is There a Direct Relationship Between Sinusitis and Muscle Pain?
- How Do You Get Staph Infection?
- What Causes an Ear Infection?
- How Do You Get an Ear Infection?
- How to Get Rid of a Staph Infection
- Urinary Tract Infection (UTI) Symptoms
- E. coli Infection Facts
- Urinary Tract Infection (UTI) Treatment
- Air Travel, Colds, and Sinus Infections
Medications & Supplements
Infectious Disease Resources
Health Solutions From Our Sponsors
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.