Amoxicillin is one of the most widely prescribed antibiotics, used for ear, throat, chest, dental, and urinary infections. It is generally well tolerated, but people often have the same questions when they pick it up: what are the side effects, what should I not take with it, and can I have a drink? This guide covers amoxicillin interactions, side effects, and alcohol in plain language.
How amoxicillin works
Amoxicillin is a penicillin-type antibiotic. It kills bacteria by stopping them from building their cell walls, which clears bacterial infections. It does nothing against viruses, so it will not help a common cold or flu — a point the CDC stresses, because taking antibiotics you do not need drives antibiotic resistance.
Common side effects
- Nausea, vomiting, or diarrhea and stomach upset.
- A mild skin rash in some people.
- Headache or an altered sense of taste.
- Thrush (a yeast infection) in the mouth or vagina, because antibiotics disturb normal flora.
Taking amoxicillin with food can ease stomach upset. If diarrhea is severe, watery, or bloody, contact your doctor, because antibiotics can occasionally trigger a more serious gut infection.
Serious effects to report
- Signs of a serious allergic reaction — hives, swelling of the face, lips, or throat, or trouble breathing (seek emergency care).
- A widespread, blistering, or peeling rash.
- Severe, watery, or bloody diarrhea, which can occur during or after treatment.
- Yellowing of the skin or eyes, or unusual bruising or bleeding.
If you have ever had a penicillin allergy, tell your prescriber before taking amoxicillin. A true penicillin allergy is an important reason this antibiotic may not be right for you.
Interactions that matter most
- Warfarin — amoxicillin can enhance its blood-thinning effect and raise bleeding risk.
- Methotrexate — amoxicillin can raise its levels, increasing the risk of toxicity.
- Allopurinol — taken together, the chance of a skin rash may increase.
- Certain other antibiotics and some live vaccines (such as oral typhoid vaccine).
- Probenecid — can raise amoxicillin levels in the blood.
How MedSafeScan helps
When a new antibiotic is added to your routine, MedSafeScan lets you check it against everything else you take — a blood thinner, methotrexate, or a regular supplement — in one place. Keeping amoxicillin on your profile also reminds every prescriber of your penicillin history, so an important allergy is never missed.
MedSafeScan provides informational guidance only and is not a substitute for professional medical advice. Always consult your healthcare provider before making any changes to your medications.
Quick answers
Can you drink alcohol while taking amoxicillin?
Unlike a few antibiotics such as metronidazole, amoxicillin does not have a dangerous reaction with alcohol, so a moderate drink is not usually considered unsafe. However, alcohol can worsen side effects like nausea and stomach upset, and it can slow your recovery from the infection you are treating, so many doctors suggest limiting or avoiding it until you feel better.
What medicines interact with amoxicillin?
Key interactions include warfarin (amoxicillin may increase bleeding risk), methotrexate (levels can rise, increasing toxicity), allopurinol (may increase the chance of a rash), and some other antibiotics. Amoxicillin can also reduce the effectiveness of certain oral typhoid vaccines. Tell your doctor and pharmacist about all your medicines and supplements before starting it.
Does amoxicillin affect birth control pills?
Current evidence suggests common antibiotics like amoxicillin do not meaningfully reduce the effectiveness of hormonal birth control for most people — this is different from the specific antibiotic rifampin. That said, vomiting or diarrhea from illness or the antibiotic could affect absorption, so using a backup method if you are sick is a reasonable precaution.
Sources and further reading
These public resources are provided for background reading. They do not replace advice from your pharmacist, doctor, or other licensed healthcare professional.
- MedlinePlus: Amoxicillin
- CDC: Antibiotic Use Questions and Answers
- FDA: Combating Antibiotic Resistance
Last reviewed: August 23, 2026