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Comparing Ampicillin vs Erythromycin

View side-by-side comparisons of medication uses, ratings, cost, side effects, interactions and more.
Ampicillin Remove Ampicillin from your drug comparison Erythromycin Remove Erythromycin from your drug comparison
View side-by-side comparisons of medication uses, ratings, cost, side effects, interactions and more.
Ampicillin Remove Ampicillin from your drug comparison Erythromycin Remove Erythromycin from your drug comparison

Prescribed for Bacterial Infection, Urinary Tract Infection, Bronchitis, Bacterial Endocarditis Prevention, Bacteremia, Gastroenteritis, Septicemia, Upper Respiratory Tract Infection, Typhoid Fever,... View more

Prescribed for Dental Abscess, Bacterial Endocarditis Prevention, Upper Respiratory Tract Infection, Skin or Soft Tissue Infection, Bronchitis, Bowel Preparation, Bartonellosis, Pemphigoid, Syphilis... View more

Prescription only

Prescription only

Ratings & Reviews

Recent helpful reviews
9.3
3 Reviews

For Urinary Tract Infection: It works and helps me get back to normal within a few hours. No side effects or drowsiness.

10
6.5
32 Reviews

For Upper Respiratory Tract Infection: I was prescribed to take the medication for sinus, inner ear, and chest infection. It made me terribly sick, so I stopped taking it. I know you're not supposed to stop and start, but I did three times. The most recent was after a medic on the set told me to eat yogurt and the sickness would subside. He said it was something in the bioflavins that helped with the nausea. My entire body felt great once I stayed on the medication as prescribed. Take care!

8

For Upper Respiratory Tract Infection: I was prescribed this medication as I have a chest infection. I had a really bad cough for around 3 weeks, after 2 days of taking this my cough was so much better. EXCEPT that around the same time my cough signifigantly improved, I felt so nauseous.

9

View all 3 reviews

View all 32 reviews

Drug Class

Side Effects

Commonly reported side effects include: eosinophilia, and skin rash.

See the full ampicillin side effects document.

See the full erythromycin side effects document.

Pricing and Coupons

* Prices are without insurance
Quantity 4 capsule
Dosage 500 mg
Per Unit* $2.02
Cost* $8.08

View all ampicillin prices

Quantity 3 tablet
Dosage 250 mg
Per Unit* $12.81
Cost* $38.44

View all erythromycin prices

Get free Discount Card

Get free Discount Card

Generic Availability

Yes (this medicine)

Yes (this medicine)

Dosage Form(s) Available
  • Injectable powder for injection
  • Oral capsule
  • Oral powder for reconstitution
  • Oral delayed release capsule
  • Oral granule for reconstitution
  • Oral tablet

Brand Names

N/A

 E-Mycin, E.E.S. Granules, E.E.S.-200, E.E.S.-400, E.E.S.-400 Filmtab, Ery-Tab, Eryc, EryPed, Erythrocin, Erythrocin Lactobionate, Erythrocin Stearate Filmtab, Erythrocot, Ilosone, MY-E, PCE Dispertab, Robimycin, Wyamycin S View more

Half Life

The half-life of a drug is the time taken for the plasma concentration of a drug to reduce to half its original value.

1.3 hours

2 hours

CSA Schedule**

View glossary of terms.
N
Not a controlled drug

Is not subject to the Controlled Substances Act.
N
Not a controlled drug

Is not subject to the Controlled Substances Act.

Pregnancy Category
B
Category B No proven risk in humans

See the full Pregnancy Warnings document.
B
Category B No proven risk in humans

See the full Pregnancy Warnings document.

FDA Alerts

N/A

N/A

Drug Interactions

A total of 84 drugs are known to interact with ampicillin:

  • 5 major drug interactions (18 brand and generic names)
  • 62 moderate drug interactions (559 brand and generic names)
  • 17 minor drug interactions (65 brand and generic names)

A total of 806 drugs are known to interact with erythromycin:

  • 224 major drug interactions (938 brand and generic names)
  • 467 moderate drug interactions (2151 brand and generic names)
  • 115 minor drug interactions (587 brand and generic names)

Alcohol/Food/Lifestyle Interactions
  • You may experience reduced absorption of ampicillin in the presence of food. The effectiveness of... View more
  • Food decreases the levels of erythromycin in your body. Take erythromycin on an empty stomach at... View more

Disease Interactions

First Approval Date

December 17, 1965

June 24, 1964

WADA Class

View World Anti-Doping Agency classifications.

N/A

N/A

More Information

Consumer Resources

Professional Resources

Related Treatment Guide

** The Controlled Substances Act (CSA) schedule information displayed applies to substances regulated under federal law. There may be variations in CSA schedules between individual states.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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