Amoxicillin Side Effects

by on January 11, 2012


Side effects associated with Amoxicillin (Amoxil) are typically mild and include nausea, dizziness and diarrhea. Some instances of diarrhea on this medication may also be linked to more severe side effects, so you should let your healthcare provider know if you are experiencing any problems on Amoxicillin or Amoxicillin based medications. Taken in moderation for infections, this is a very effective treatment. However, using Amoxicillin frequently can decrease its overall effectiveness. Be sure to let your doctor know if you have taken amoxicillin medications before.

Common Amoxicillin Side Effects

Common side effects of Amoxicillin are mild and generally go away on their own. These include the following:

  • Diarrhea
  • Nausea
  • Vomiting
  • Dizziness
  • Insomnia
  • Tooth discoloration
  • Black, hairy tongue
  • Hyperactivity
  • Confusion

If the above side effects persist, worsen or seriously disrupt your everyday life, you should contact your doctor. Do not take anti-diarrheal medication while taking Amoxicillin. Diarrhea that is watery or bloody is of a particular concern and should be brought the attention of your doctor. Always tell your doctor if you choose to stop taking Amoxil or amoxicillin as your infection may still need to be treated.

Serious Amoxicillin Side Effects

Amoxicillin Side EffectsSome patients experience an allergic reaction to amoxicillin. If you are allergic to other penicillin antibiotics like dicloxacilin or ampicilin, you should consult your doctor as you may be allergic to amoxicillin as well. The following side effects may indicate an allergic reaction:

  • Rash or hives
  • Itchiness
  • Difficulty breathing
  • Tightness in the chest
  • Swelling of the face or throat

If you believe you are experiencing an allergic reaction, you should see a healthcare professional immediately. Other serious side effects that should be reported to your doctor include the following:

  • Seizures
  • Unexplained anxiety
  • Yellowing of the eyes or skin
  • Dark-colored urine
  • Abdominal pain
  • Bloody or watery diarrhea (even if it occurs after your have completed the medication)

Amoxil and Birth Control

One of the common side effects of amoxicillin effects is reduced effectiveness of birth control medications. If you are relying solely on a birth control pill, ring or patch to prevent pregnancy, you should talk to your doctor. You may need to use a secondary method of birth control, such as condoms, until you have completed your Amoxicillin regimen.


One of the more common amoxicillin side effects is a rash. Since it is difficult to distinguish a harmless rash from one indicative of an allergic reaction, you should see your doctor if any type of rash develops. Patients with mononucleosis (mono) are more likely to develop a rash. It is generally recommended that individuals with mono avoid taking amoxicillin medications.

Yeast Infections

Prolonged or repeated use of amoxicillin can cause a vaginal yeast infection or yeast infection of the mouth. Amoxicillin  does not discriminate between good and bad bacteria. When the beneficial bacteria in the body are killed off, it is common for a yeast infection to occur. If you experience either of these Amoxil side effects, you should contact your heathcare provider.


In rare cases, Clostridium difficile-associated diarrhea could occur as a result of Amoxicillin use. This complication may occur days, weeks or even months after the amoxicillin treatment has been completed. If you experience any of the following symptoms, you should contact your healthcare provider immediately. Avoid self-treatment with an anti-diarrheal as this will only aggravate the problem. Symptoms of this complication include:

  • Blood or mucus in the stool
  • Cramps
  • Abdominal pain
  • Persistent diarrhea

Amoxicillin are time-tested antibacterial medications that are safe for most patients. Always complete your entire dosage to reap the full effects of these drugs. If you experience adverse side effects, consult your doctor to discuss your options. Stopping Amoxicillin early could result in a relapse of your original infection.