- Bacterial Infections 101 Pictures Slideshow
- Take the Tummy Trouble Quiz
- Hepatitis C Slideshow Pictures
- Amoxicillin vs. penicillin: What's the difference?
- What is amoxicillin? What is penicillin?
- What are the side effects of amoxicillin vs. penicillin?
- What is the dosage of amoxicillin vs. penicillin?
- What drugs interact with amoxicillin and penicillin?
- Are amoxicillin and penicillin safe to use while pregnant or breastfeeding?
Amoxicillin vs. penicillin: What's the difference?
- Amoxicillin and penicillin are penicillin-type antibiotics used to treat various bacterial infections of the middle ear, sinuses, urinary tract, and respiratory tract. They are also used to treat gonorrhea.
- Penicillin-type antibiotics are also used to treat blood infections (sepsis), meningitis, endocarditis, and other serious infections.
- Brand names of amoxicillin include Moxatag and Amoxil.
- Side effects of amoxicillin and penicillin are similar and include diarrhea, dizziness, heartburn, sleep problems (insomnia), abdominal pain, nausea, vomiting, itching, confusion, easy bruising, bleeding, rash, and allergic reactions.
What is amoxicillin? What is penicillin?
Amoxicillin is a penicillin-type antibiotic, in the same drug 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 bacteria from forming the walls that surround them. The walls protect bacteria from their environment and keep the contents of the bacterial cell together. Amoxicillin is effective against different bacteria including H. influenzae, N. gonorrhoea, E. coli, Pneumococci, Streptococci, and some strains of Staphylococci. Amoxicillin is used to treat bacterial infections of the middle ear, tonsils, throat, larynx (laryngitis), respiratory tract, urinary tract, and skin. Amoxicillin also is used to treat gonorrhea.
Penicillin antibiotics are used to treat many types of bacterial infections of the middle ear, sinuses, stomach and intestines, bladder, and kidney. They also are used to treat pneumonia, blood infections (sepsis), uncomplicated gonorrhea, meningitis, endocarditis, and other serious infections. Many derivatives of penicillin have been developed that inhibit more types of bacteria than the original life-saving drug. Penicillin itself is active against streptococci (including Streptococcus pneumoniae), Listeria, Neisseria gonorrhoeae, Clostridium, Peptococcus, and Peptostreptococcus.
What are the side effects of amoxicillin vs. penicillin?
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.
Side effects of penicillin antibiotics include
- abdominal pain,
- easy bruising,
- rash, and
- allergic reactions.
Individuals 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
- kidney problems,
- oral fungal infections,
- severe allergic reactions (anaphylaxis), and
- low blood platelet levels (thrombocytopenia) or red blood cell count.
Like other antibiotics, penicillin 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 (C. difficile colitis or pseudomembranous colitis).
Signs and symptoms of C. difficile colitis include
Latest Infectious Disease News
- Ground Turkey Linked to Salmonella Outbreak
- Doctors': Antibiotics Can Be for Shorter Periods
- Salmonella Outbreak Linked to Songbirds & Feeders
- Sabra Classic Hummus Recalled Due to Salmonella
- Ebola Survivor May Have Started Latest Outbreak -- 5 Years Later
- Want More News? Sign Up for MedicineNet Newsletters!
Daily Health News
What is the dosage of amoxicillin vs. penicillin?
- 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.
Penicillin antibiotics are available as
- powder for oral suspension, and
- powder for injection.
What drugs interact with amoxicillin and penicillin?
Amoxicillin is rarely associated with important drug interactions.
Penicillin antibiotics have few important drug interactions.
- Probenecid (Benemid) causes an increase in the amount of penicillins in the body by preventing excretion of penicillin by the kidneys.
- Combining ampicillin with allopurinol (Zyloprim) can increase the incidence of drug-related skin rash.
- Penicillin antibiotics may reduce the effect of BCG live vaccine and typhoid live vaccine.
Are amoxicillin and penicillin 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.
- Penicillin antibiotics are considered safe to use during pregnancy.
- Although small amounts of penicillins pass into breast milk they are considered safe to use while breastfeeding.
Subscribe to MedicineNet's General Health Newsletter
Amoxicillin and penicillin are penicillin-type antibiotics used to treat various bacterial infections of the middle ear, sinuses, urinary tract, and respiratory tract. They are also used to treat gonorrhea. Penicillin-type antibiotics are also used to treat blood infections (sepsis), meningitis, endocarditis, and other serious infections.
Multimedia: Slideshows, Images & Quizzes
Common Eye Problems and Infections
Eye diseases can cause damage and blindness if not detected and treated soon enough. Learn the warning signs and symptoms of...
Bacterial Infections 101: Types, Symptoms, and Treatments
Get more information on bacterial skin infections, which bacteria cause food poisoning, sexually transmitted bacteria, and more....
Ear Infection Symptoms, Causes, and Treatment
Learn about the causes and symptoms of ear infections and how they are diagnosed and treated. Read about treatments such as ear...
Respiratory Illnesses: 13 Types of Lung Infections
Is your cough caused by a cold, flu, pneumonia or something else? Learn causes of respiratory infection like bronchitis,...
Bladder Infections: UTI Causes, Symptoms, Treatments
Urinary tract infections (UTI), including bladder infections, affect women and men, causing UTI symptoms like kidney infection....
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
H. pylori (Helicobacter Pylori) Infection
Helicobacter pylori (H. pylori) is a bacteria that causes chronic inflammation (gastritis) of the inner lining of the stomach, and also is the most common cause of ulcers worldwide. About 50% of people in the world carries or is infected with H. pylori. Common symptoms of H. pylori infection are occasional abdominal discomfort, bloating, belching or burping, and nausea and vomiting. H. pylori infection is difficult to eradicate, and treatment is with two or more antibiotics.
Inner Ear Infection (Symptoms, Signs, Treatments, Home Remedies)
An inner ear infection or otitis interna is caused by viruses or bacteria and can occur in both adults and children. An inner ear infection can cause symptoms and signs, for example, a severe ear, dizziness, vertigo, nausea and vomiting, and vertigo. An inner ear infection also may cause inflammation of the inner ear or labyrinthitis. Inner ear infections are not contagious; however, the bacteria and viruses that cause the infection can be transmitted to other people. Good hygiene practices will help decrease the chances of the infection spreading to others. Inner ear infection symptoms and signs like ear pain and nausea may be relieved with home remedies or over the counter (OTC) medication. Some inner ear infections will need to be treated and cured with antibiotics or prescription pain or antinausea medication.
Upper Respiratory Tract Infection (URTI)
An upper respiratory infection is a contagious infection of the structures of the upper respiratory tract, which includes the sinuses, nasal passages, pharynx, and larynx. Common causes of an upper respiratory infection include bacteria and viruses such as rhinoviruses, group A streptococci, influenza, respiratory syncytial, whooping cough, diphtheria, and Epstein-Barr. Examples of symptoms of upper respiratory infection include sneezing, sore throat, cough, fever, and nasal congestion. Treatment of upper respiratory infections are based upon the cause. Generally, viral infections are treated symptomatically with over-the-counter (OTC) medication and home remedies.
Middle Ear Infection (Otitis Media)
Middle ear infection (otitis media) is inflammation of the middle ear. There are two forms of this type of ear infection, acute and chronic. Acute otitis media is generally short in duration, and chronic otitis media generally lasts several weeks. Babies, toddlers, and children with a middle ear infection may be irritable, pull and tug at their ears, and experience numerous other symptoms and signs. Treatment depends upon the type of ear infection.
Urinary Tract Infection (UTI)
A urinary tract infection (UTI) is an infection of the bladder, kidneys, ureters, or urethra. E. coli, a type of bacteria that lives in the bowel and near the anus, causes most UTIs. UTI symptoms include pain, abdominal pain, mild fever, urinary urgency and frequency. Treatment involves a course of antibiotics.
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 (otitis media) infections can be treated at home with remedies like warm compresses for ear pain relief, tea tree, ginger, or garlic oil drops. Symptoms of an outer ear (swimmer's ear) and middle ear infection include mild to severe ear pain, pus draining from the ear, swelling and redness in the ear, and hearing problems. Middle and inner ear infections may cause fever, and balance problems. Inner ear infections also may cause nausea, vomiting, vertigo, ringing in the ear, and labyrinthitis (inflammation of the inner ear). Most outer and middle ear infections do not need antibiotics. Inner ear infections should be treated by a doctor specializing in ear and hearing problems.
Kidney Infection (Pyelonephritis)
Kidney infection (pyelonephritis) usually is caused by E. coli and other bacteria that have spread from the bladder from a UTI (urinary tract infection), poor hygiene, sexual intercourse, pregnancy, catheter, cystoscope exam, surgery, kidney stones, or prostate enlargement. Symptoms of kidney infection include back pain, frequent urination, pain during urination, fever, and or pus or blood in the urine. Kidney infection can be cured with antibiotic treatment. Cranberry juice may prevent UTIs, but that hasn’t been proven in all research studies.
Is a Staph Infection Contagious?
A staph infection is caused by the bacteria Staphylococcus aureus. Staph can cause boils, food poisoning, cellulitis, toxic shock syndrome, MRSA, and various other illnesses and infections. Most staph infections are transmitted from person to person.
Dog Bite (Infections, Symptoms, Treatment, Management)
A dog bites about 4.5 million people each year, and about 27,000 will need surgery. Dog bites often become infected, and will need medical treatment and management. Make sure that the dog’s rabies vaccination is current; if not, rabies treatment may be necessary. A dog bite may cause symptoms and signs like puncture wounds, lacerations, pain, swelling, and redness. Treatment and management of a dog bite in and infant, child, teen, or adult depends upon the severity of the wound. Dog bites can be prevented by not approaching stray or unfamiliar dogs, especially if the dog is eating, sleeping, or caring for puppies; always ask the dog owner if you can pet the dog, and do not make eye contact, run, or scream if a dog if you are confronted with a dog.
Is a Urinary Tract Infection (UTI) Contagious?
Bacteria such as E. coli or Pseudomonas can cause a urinary tract infection (UTI). The incubation period for a UTI ranges from three to eight days.
Urinary Tract Infections in Children
Urinary tract infections (UTIs) are very common in children. Symptoms and signs include fever and abdominal pain. Associated symptoms and signs include flank pain, vomiting, and blood in the urine. Treatment for a UTI involves antibiotic therapy.
Bladder Infection (Cystitis)
Bladder infection is an infection of the bladder, usually caused by bacteria or, rarely, by Candida. Certain people, including females, the elderly, men with enlarged prostates, and those with chronic medical conditions are at increased risk for bladder infection. Bladder infections are treated with antibiotics, but cranberry products and adequate hydration may help prevent bladder infections.
Group A Streptococcal Infections
Second Source article from Government
Is a Sinus Infection Contagious?
Sinus infection (sinusitis) is infection (viral, bacterial, or fungal) or inflammation of the sinuses. Symptoms of sinus infection are cough, bad breath, coughing up greenish-yellow sputum, sinus headache, and other symptoms of the common cold. Treatments of sinus infection are home remedies to soothe symptoms and antibiotics if the infection is bacterial or fungal.
Treatment & Diagnosis
- Ear Infection FAQs
- What Is the Difference Between a Bladder Infection vs. UTI?
- 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
- Do They Test for Infection in an Autopsy?
- Flesh Eating Bacterial Infection
- Urinary Tract Infection (UTI) Symptoms
- E. coli Infection Facts
- Urinary Tract Infection (UTI) Treatment
- Air Travel, Colds, and Sinus Infections
Medications & Supplements
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.