Ampicilline Uses, Dosage, Side Effects, Food Interaction and all others data.

Ampicilline inhibits bacterial cell wall synthesis by binding to 1 or more of the penicillin-binding proteins (PBPs) which in turn inhibit the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls. Bacteria eventually lyse due to ongoing activity of cell wall autolytic enzymes (autolysins and murein hydrolases) while cell wall assembly is arrested.

Ampicilline is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. The name "penicillin" can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Ampicilline has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of Ampicilline results from the inhibition of cell wall synthesis and is mediated through Ampicilline binding to penicillin binding proteins (PBPs). Ampicilline is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases.

Trade Name Ampicilline
Availability Prescription only
Generic Ampicillin
Ampicillin Other Names ABPC, Aminobenzylpenicillin, Ampicilina, Ampicillin, Ampicillin acid, Ampicilline, Ampicillinum
Related Drugs amoxicillin, prednisone, doxycycline, ciprofloxacin, cephalexin, metronidazole, azithromycin, clindamycin, ceftriaxone, levofloxacin
Formula C16H19N3O4S
Weight Average: 349.405
Monoisotopic: 349.109626801
Groups Approved, Vet approved
Therapeutic Class Broad spectrum penicillins
Available Country
Last Updated: September 19, 2023 at 7:00 am


Ampicilline is used for the treatment of infections caused by susceptible strains of the designated organism listed below:

  • Infections of the Genitourinary Tract Including Gonorrhea: E. coli, P. mirabilis, enterococci, Shigella, S. typhosa and other Salmonella, and nonpenicillinase-producing N. gononhoeae.
  • Infections of the Respiratory Tract: Nonpenicillinase-producing H. influenzae and staphylococci, and streptococci including streptococcus pneumoniae.
  • Infections of the Gastrointestinal Tract: Shigella, S. typhosa and other Salmonella, E. coli, P. mirabilis, and enterococci.
  • Meningitis: O. Meningitides.

Bacteriology studies to determine the causative organisms and their sensetivity to ampicillin should be performed. Therapy may be instituted prior to the results of susceptibility testing.

Ampicilline is also used to associated treatment for these conditions: Bacterial Infections, Bloodstream Infections, Endocarditis, Gastrointestinal Infections, Genitourinary tract infection, Infection, Infection caused by eikenella corrodens, Listeria infection, Meningitis, Bacterial, Pertussis, Respiratory Tract Infections (RTI), Salmonella, Salmonella Typhi Infection, Shigella, Skin Infections, Bacterial, Subcutaneous bacterial infection, Urinary Tract Infection, Perinatal group B streptococcus, Susceptible Bacterial Infections

How Ampicilline works

By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, Ampicilline inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that Ampicilline interferes with an autolysin inhibitor.


Ampicilline dosage

Intra-articular:Supplement in systemic therapy for treatment of susceptible infections-

  • Adult:500 mg daily.
  • Child:<10 yrHalf of adult routine dosage.


Supplement in systemic therapy for treatment of susceptible infections-

  • Adult:500 mg daily.
  • Child:<10 yrHalf of adult routine dosage.


Supplement in systemic therapy for treatment of susceptible infections-

  • Adult:500 mg daily.
  • Child:<10 yrHalf of adult routine dosage



  • Adult:2 gm 6 hrly.
  • Child:150 mg/kg daily in divided doses.

Intrapartum prophylaxis against group B Streptoccocal infection in neonates-

  • Adult:Initially, 2 gm via IV inj followed by 1 gm 4 hrly until delivery.


Biliary tract infections, Bronchitis, Endocarditis, Gastroenteritis, Listeriosis, Otitis media, Perinatal streptococcal infections, Peritonitis-

  • Adult:0.25-1 gm 6 hrly.
  • Child:<10 yrHalf of adult routine dosage.

Typhoid and paratyphoid fever-

  • Adult:1-2 gm 6 hrly for 2 wk in acute infections, and 4-12 wk in carriers.

Uncomplicated gonorrhoea-

  • Adult:2 gm with 1 gm of probenecid as single dose, recommended to be repeated in female patients.

Urinary tract infections-

  • Adult:500 mg 8 hrly.


Susceptible infections-

  • Adult:500 mg 6 hrly, via IM or slow IV inj over 3-5 min or by infusion.
  • Child:<10 yrHalf of adult routine dosage.


  • Adult:150-200 mg/kg daily. Initiate with IV admin for at least 3 days, then continue with IM inj 3-4 hrly. Continue treatment for at least 48-72 hr after the patient has become asymptomatic or when there is evidence of bacterial eradication. Recommended treatment duration for infections caused by group-A β-haemolytic streptococci: At least 10-days, to prevent occurrence of acute rheumatic fever or acute glomerulonephritis.
  • Child:Same as adult dose.

Should be taken on an empty stomach. Take 1 hr before or 2 hr after meals.

Intramuscular: Add 1.5 mL water for inj to 500 mg vial contents.

Intravenous: Dissolve 500 mg in 10 mL water for inj. May be added to infusion fluids or injected, suitably diluted into the drip tube.

Intra-articular: Dissolve 500 mg in up to 5 mL of water for inj or sterile procaine HCl 0.5% soln.

Intraperitoneal: Dissolve 500 mg in up to 10 mL water for inj.

Intrapleural: Dissolve 500 mg in 5-10 mL water for inj.

Side Effects

Nausea, vomiting, diarrhoea, erythematous maculo-papular rashes, sore mouth, black/hairy tongue, rash, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, angioedema, fever, joint pains, serum sickness-like symptoms, haemolytic anaemia, thrombocytopenia, leucopenia, neutropenia, coagulation disorders, prolonged bleeding time and prothrombin time, CNS toxicity (e.g. convulsions); paraesthesia, nephropathy, interstitial nephritis, hepatitis, cholestatic jaundice, moderate and transient increase in transaminases, Anaphylaxis, Clostridium difficile-associated diarrhoea (CDAD).


Patient with history of β-lactam allergy. During renal impairment, Pregnancy and lactation.


May reduce the efficacy of oral contraceptives. May alter INR while on warfarin and phenindione. May reduce the efficacy of oral typhoid vaccines. May reduce the excretion of methotrexate. Reduced excretion with probenecid and sulfinpyrazone, resulting to increased risk of toxicity. Allopurinol increases ampicillin-induced skin reactions. Reduced absorption with chloroquine. Bacteriostatic antibacterials (e.g. erythromycin, chloramphenicol, tetracycline) may interfere with the bactericidal action of ampicillin.

Food Interaction

  • Take on an empty stomach.

[Moderate] ADJUST DOSING INTERVAL: Certain penicillins may exhibit reduced gastrointestinal absorption in the presence of food.

The therapeutic effect of the antimicrobial may be reduced.

MANAGEMENT: The interacting penicillin should be administered one hour before or two hours after meals.

Penicillin V and amoxicillin are not affected by food and may be given without regard to meals.

Ampicilline Hypertension interaction

[Moderate] Parenteral ampicillin sodium contains approximately 67 to 71 mg (2.9 to 3.1 mEq) of sodium per each gram of ampicillin activity.

The combination, ampicillin-sulbactam, contains approximately 115 mg (5 mEq) of sodium per 1.5 gram of total drug.

The sodium content should be considered when these products are used in patients with conditions that may require sodium restriction, such as congestive heart failure, hypertension, and fluid retention.

Elimination Route

Ampicilline is excreted largely unchanged in the urine.

Pregnancy & Breastfeeding use

Pregnancy Category B. Either animal-reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).


Hypersensitivity to ampicillin and other penicillins.

Special Warning

Renal Impairment: CrCl<10: Dose reduction or increase in dose interval.

Acute Overdose

Symptoms: Nausea, vomiting and diarrhoea. Management: Symptomatic and supportive treatment. May be removed from the circulation by haemodialysis.

Storage Condition

Store between 20-25° C. Reconstituted oral susp: Store between 2-8° C (discard after 14 days).

Innovators Monograph

You find simplified version here Ampicilline

Ampicilline contains Ampicillin see full prescribing information from innovator Ampicilline Monograph, Ampicilline MSDS, Ampicilline FDA label


What is Ampicilline used for?

Ampicilline is an antibiotic used to prevent and treat a number of bacterial infections, such as respiratory tract infections, urinary tract infections, meningitis, salmonellosis, and endocarditis. It may also be used to prevent group B streptococcal infection in newborns. Ampicilline may also be used for purposes not listed in this medication guide.

How safe is Ampicilline?

In accordance with other studies, Ampicilline was well tolerated, with mild diarrhea reported in 14% and skin rash in 3% of patients. Thus, Ampicilline appears to provide effective and safe therapy for the treatment of infections caused by aerobic and anaerobic pathogens.

How does Ampicilline work?

Ampicilline works by interfering with the ability of bacteria to form cell walls. Ampicilline allows holes to appear in the bacterial cell walls and this kills the bacteria causing the infection. Ampicilline is a broad-spectrum antibiotic, which means it kills a wide variety of different types of bacteria.

What are the common side effects of Ampicilline?

Common side effects of Ampicilline are include:

  • acute inflammatory skin eruption (erythema multiforme)
  • redness and peeling of the skin (exfoliative dermatitis)
  • rash
  • hives
  • fever
  • seizure
  • black hairy tongue
  • diarrhea
  • inflammation of the small intestine and colon
  • inflammation of the tongue
  • nausea
  • yeast infection in the mouth (oral candidiasis/thrush)
  • swelling or inflammation of the large intestine/colon
  • inflammation of the mouth
  • vomiting
  • low white blood cell count (agranulocytosis)
  • anemia
  • low red blood cell count (anemia)
  • high white blood cell count (eosinophilia)
  • reduction of white blood cells (leukopenia)
  • acute allergic reaction (anaphylaxis)
  • elevated aspartate aminotransferase (AST)
  • inflammation in the kidney
  • noisy breathing
  • allergic reaction
  • headache
  • vaginal itching or discharge
  • dark urine
  • easy bruising or bleeding
  • persistent sore throat or fever

Is Ampicilline safe during pregnancy?

Ampicilline is considered safe during pregnancy. If Ampicilline is used during pregnancy, the potential benefit of Ampicilline for the mother should be weighed against the potential risk of side effects in the infant.

Is Ampicilline safe during breastfeeding?

Ampicilline is acceptable in nursing mothers.

Can I drink alcohol with Ampicilline?

Yes, you can drink alcohol while taking the Ampicilline. The alcohol will not stop Ampicilline from working. Moderation is key. However, many health professionals will recommend you avoid alcohol to give your body the best chance possible to fight the infection.

Can I drive after taking Ampicilline?

You should not drive or operate machinery if you're taking an antibiotic that makes you drowsy.

When is the best time to take Ampicilline?

Take this Ampicilline by mouth usually 4 times a day (every 6 hours), or as directed by your doctor. Take Ampicilline on an empty stomach (1 hour before or 2 hours after a meal) with a full glass of water.

Is Ampicilline taken on an empty stomach?

Take Ampicilline on an empty stomach, at least 30 minutes before or 2 hours after a meal.

Does Ampicilline make me sleepy?

Ampicilline oral capsule doesn't cause drowsiness, but it can cause other side effects.

How long does Ampicilline take to work?

Ampicilline will start working right away to fight the infection in your body. You should start to feel better after 2 days, but continue to take the full course of your medication even if you feel like you don't need it anymore.

How long does Ampicilline stay in my system?

Ampicilline stays in your body for up to 8 hours and is then removed when you urinate.

Do Ampicilline keep working after I stop taking them?

It's important to complete the full course of antibiotics, even if you begin to feel better beforehand. Because if you discontinue the treatment early you may not eliminate enough bacteria, and the condition could re-occur, as surviving bacteria multiply.

Can I take Ampicilline for a long time?

Use this Ampicilline  for the full prescribed length of time, even if your symptoms quickly improve. Skipping doses can increase your risk of infection that is resistant to medication.

How long can I take Ampicilline ?

Ampicilline should be taken for 7 to 14 days.

Who should not take Ampicilline?

You should not use Ampicilline if you are allergic to Ampicilline. Tell your doctor if you have ever had: diabetes, hay fever.

What happens if I miss a dose?

Take the Ampicilline as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happen if I take too much Ampicilline?

Symptoms of an overdose of this drug can include upset stomach and diarrhea. If you think you've taken too much of this drug, call your doctor or local poison control center. If your symptoms are severe, call your doctor or go to the nearest emergency room right away.

What happen If I suddenly stop taking Ampicilline?

If you stop taking the Ampicilline suddenly or don't take it at all: Your bacterial infection may not get better. It may even get worse.

Will Ampicilline affect my fertility?

Ampicilline affect both the quantity and quality of sperm. They may reduce the number of sperm a man produces, and make the sperm he does produce swim more slowly.

Can Ampicilline affect my kidneys?

The Ampicilline observed after high doses of ampicillin caused renal failure by tubular obstruction.

Can Ampicilline affects my liver?

Ampicilline has been linked with idiosyncratic liver injury, but very rarely and in largely in isolated case reports.

*** Taking medicines without doctor's advice can cause long-term problems.