Side Effects of Amoxicillin - Amoxicillin

Amoxicillin is an antibiotic effective against various bacterial infections, including ear infections, strep throat, and pneumonia. While it is generally well-tolerated, like all medications, it can cause side effects ranging from mild to severe. Understanding these side effects and how to manage them is crucial for ensuring a safe treatment experience.

Possible Side Effects

Like all medicines, Amoxicillin can cause side effects, although not everybody gets them. The following side effects may happen with this medicine. Tell your healthcare professional if any of the following side effects happen to you:

Common (reported less than 1 in 10 people): skin rash, diarrhea, and feeling sick (nausea).

Uncommon (reported less than 1 in 100 people): being sick (vomiting).

Very rare (reported less than 1 in 10,000 people):

thrush (a yeast infection of the vagina, mouth, or skin folds), you can get treatment for thrush from your doctor or pharmacist;
kidney problems;
fits (convulsions), seen in patients on high doses or with kidney problems;
dizziness;
hyperactivity;
crystals in the urine, which may be seen as cloudy urine or difficulty or discomfort in passing urine. Make sure you drink plenty of fluids to reduce the chance of these symptoms;
teeth may appear stained, usually returning to normal with brushing (this has been reported in children);
the tongue may change to yellow, brown, or black, and it may have a hairy appearance;
an excessive breakdown of red blood cells, causing a form of anemia. Signs include tiredness, headaches, shortness of breath, dizziness, looking pale and yellowing of the skin and the whites of the eyes;
the blood may take longer to clot than it normally would. You may notice this if you have a nosebleed or cut yourself.

Serious Side Effects

Stop taking Amoxicillin and see a doctor straight away if you notice any of the following serious side effects (you may need urgent medical treatment):

The following are very rare (affects less than 1 in 10,000 people):

allergic reactions, the signs may include swelling of the face, lips, tongue, body, skin itching or rash, or breathing difficulties. These can be serious, and occasionally deaths have occurred;
rash or pinpoint flat red round spots under the skin surface or bruising of the skin. This is due to inflammation of blood vessel walls due to an allergic reaction. It can be associated with joint pain (arthritis) and kidney problems;
a delayed allergic reaction can occur 7 to 12 days after having Amoxicillin; some signs include rashes, fever, joint pains, and enlargement of the lymph nodes, especially under the arms;
a skin reaction known as ‘erythema multiforme’ where you may develop itchy reddish-purple patches on the skin, especially on the palms of the hands or soles of the feet, ‘hive-like’ raised swollen areas on the skin, tender areas on the surfaces of the mouth, eyes and private parts. You may have a fever and be very tired;
other severe skin reactions can include: changes in skin color, bumps under the skin, blistering, pustules, peeling, redness, pain, itching, and scaling. These may be associated with fever, headaches, and body aches;
high temperature (fever), chills, a sore throat, or other signs of an infection, or if you bruise easily. These may be signs of a problem with your blood cells;
inflammation of the large bowel (colon) with diarrhea, sometimes containing blood, pain and fever;
serious liver side effects may occur, which are often reversible. They are mainly associated with people having treatment over a long period, males, and the elderly. You must tell your doctor urgently if you get severe diarrhea with bleeding, blisters, redness or bruising, darker urine or paler stools, yellowing of the skin, or the whites of the eyes (jaundice);
abdominal or stomach cramps or tenderness;
black, tarry stools, clay-colored stools, watery or bloody diarrhea;
fast heartbeat;
back, leg, or stomach pains;
hives or welts;
bleeding gums;
inflammation of the joints, joint or muscle pain, muscle aches;
bloody nose;
the feeling of discomfort;
blistering, peeling, or loosening of the skin;
bloating, nausea or vomiting, vomiting of blood;
heavier menstrual periods;
dark urine, blood in the urine, painful or difficult urination, sudden decrease in the amount of urine;
chest pain, dizziness, difficulty with breathing, difficulty with swallowing, tightness in the chest, unpleasant breath odor;
wheezing;
general body swelling;
welting, or blisters;
sore throat, sores, ulcers, or white spots in the mouth or on the lips;
increased thirst;
unusual bleeding or bruising;
itching, pale skin, pinpoint red spots on the skin, rash, redness, soreness, or itching skin;
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue;
red, irritated eyes;
swollen lymph glands;
unusual tiredness or weakness;
loss of appetite, unusual weight loss;
yellow eyes or skin.

Incidence not known:

black, hairy tongue;
agitation;
confusion;
changes in behavior;
discoloration of the tooth (brown, yellow, or gray staining);
convulsions;
sleeplessness, unable to sleep;
dizziness;
white patches in the mouth or throat or on the tongue, white patches with diaper rash.

Amoxicillin Adverse Effects on Body System

In clinical practice, understanding the side effects of medications is crucial for optimizing patient care and ensuring safety. This abstract presents a comprehensive overview of adverse effects categorized by body system, highlighting the varying frequencies of occurrence. By organizing these side effects systematically, healthcare professionals can better anticipate potential reactions and make informed decisions regarding treatment options.

System	Common (1% to 10%)	Uncommon (0.1% to 1%)	Very Rare (<0.01%)	Frequency Not Reported
Gastrointestinal	Diarrhea, nausea, abdominal pain	Vomiting	Hemorrhagic/pseudomembranous colitis, tooth discolored, black hairy tongue, glossitis, stomatitis	Sore mouth/tongue
Dermatologic	Erythema, exanthema, rash	Urticaria, pruritus	Angioedema, hypersensitivity vasculitis	Erythematous maculopapular rashes, erythema multiforme, Stevens-Johnson Syndrome, bullous dermatitis, exfoliative dermatitis, toxic epidermal necrolysis/Lyell’s syndrome, acute generalized exanthematous pustulosis, maculopapular rash, erythema nodosum, pemphigoid reactions
Genitourinary	Vulvovaginal mycotic infection
Nervous System	Headache, taste perversion		Convulsion, dizziness, hyperkinesia	Reversible hyperactivity, central nervous system toxicity, encephalopathy
Immunologic			Anaphylaxis, serum sickness-like reaction	Jarisch-Herxheimer reaction
Renal			Crystalluria, interstitial nephritis	Nephropathy
Hematologic			Leucopenia, severe neutropenia, agranulocytosis, hemolytic anemia, thrombocytopenia, bleeding time prolonged, prothrombin time prolonged	Anemia, thrombocytopenic purpura, eosinophilia, platelet function defective, lymphadenopathy
Other	Candidiasis, fungal/mycotic infection		Mucocutaneous candidiasis	Intestinal candidiasis, oral moniliasis, vaginal moniliasis, fever, chills
Hepatic			Hepatitis, cholestatic jaundice, AST increased, ALT increased	Hepatic dysfunction, hepatic cholestasis, acute cytolytic hepatitis
Respiratory				Bronchospasm, acute severe dyspnea, pneumonitis allergic
Local				Phlebitis, injection site pain
Metabolic				Electrolyte disturbance, hypokalemia
Musculoskeletal				Joint pain, arthralgia
Psychiatric				Agitation, anxiety, insomnia, confusion, behavior changed, hallucination

How to Manage Side Effects

Managing side effects is a critical component of effective medication therapy, as nearly all medications can produce unwanted reactions that may impact patient adherence and overall health. To effectively manage the side effects of Amoxicillin, it is essential to understand both the common and severe reactions associated with this antibiotic.

Management of Common Side Effects

Below is the list of common side effects of Amoxicillin and their management:

nausea and vomiting: eat simple meals and avoid rich or spicy foods. Taking Amoxicillin after meals may help reduce nausea;
diarrhea: stay hydrated by drinking plenty of fluids like water or oral rehydration solutions. Avoid self-medicating with over-the-counter anti-diarrheal medications without consulting a healthcare professional.
skin rash: mild rashes can often be treated with antihistamines (e.g., diphenhydramine) or hydrocortisone cream. If the rash is severe or accompanied by other symptoms like difficulty breathing, seek medical attention immediately;
headaches: pain relievers like acetaminophen or ibuprofen can be used to alleviate headaches, but consult your doctor if they persist;
changes in taste: this side effect is usually temporary and resolves after discontinuing the medication. If it becomes bothersome, consult your healthcare provider for advice.

Management of Serious Side Effects

While most side effects of Amoxicillin are mild and manageable, some can be serious:

Severe diarrhea: This may indicate a condition known as Clostridioides difficile infection (C. diff). Contact your doctor if you experience watery or bloody stools, especially if they are accompanied by fever or stomach cramps.
Allergic reactions: Symptoms such as hives, swelling of the face or throat, and difficulty breathing require immediate medical attention. If you have a known allergy to penicillin, inform your healthcare provider before starting treatment.

When to Seek Medical Help

If you experience any severe or persistent side effects, it’s crucial to contact your healthcare professional for guidance. They may adjust your treatment plan or suggest alternative medications if necessary.

When taking amoxicillin, it is crucial to follow the prescribed form and dosage as directed by your healthcare provider to ensure effective treatment and minimize the risk of side effects. Remember, improper use of antibiotics like amoxicillin can contribute to antibiotic resistance, making future infections harder to treat.

Additionally, be sure to read about any precautions associated with the medication, as they can help you understand potential risks and necessary monitoring during treatment.

It is also important to discuss any possible interactions with other medications you are taking, as this can affect the efficacy of amoxicillin or increase the risk of adverse effects.

Lastly, be aware of contraindications for amoxicillin, particularly if you have a history of allergies to penicillin or other related antibiotics, as this could lead to serious allergic reactions.

If you still have questions about Amoxicillin, check our FAQ’s to get more information.