Ampicillin 125 mg per 5 mL (suspension) Dosage Calculator

How to Calculate Ampicillin 125 mg per 5 mL (suspension) Dose

This calculator determines the Ampicillin dose for treating bacterial infections, using a concentration of 125 mg per 5 mL (25 mg/mL), based on the patient’s weight and dosing range of 50 to 100 mg/kg/day PO QID (maximum 2 g/day):

Dose in mg and Volume in mL:

Daily Dose (mg) = Weight (kg) × Dose (mg/kg/day)

Per Dose (mg) = Daily Dose ÷ 4 (QID, every 6 hours)

Volume (mL) = Per Dose (mg) ÷ 25 mg/mL

Where:

Weight: Patient’s weight in kg or lb (converted to kg, minimum 1 kg).
Dose Selection: 50, 60, 70, 80, 90, or 100 mg/kg/day PO QID (Max: 2g/day).
Frequency: QID (4 times daily, every 6 hours).
Concentration: 25 mg/mL.

For adults (weight ≥ 40 kg), use 500 mg po every 6 hours. Administer for 7–10 days, or as directed. ⚠️ Always consult a healthcare provider.

Using the Ampicillin 125 mg per 5 mL (suspension) Dosage Calculator

Enter the patient’s weight, select the dose (50, 60, 70, 80, 90, or 100 mg/kg/day PO QID). The calculator provides the dose in mL and mg per dose for pediatric patients (> 3 months) or adults, formatted as 'Dose,' 'Min Dose,' and 'Max Dose' po every 6 hours. The 'Min Dose' and 'Max Dose' are calculated based on 50 mg/kg/day and 100 mg/kg/day, respectively.

Example: Weight 12 kg, 100 mg/kg/day PO QID:

Pediatric ≥ 3 months:
Dose: 6 mL (150 mg) po every 6 hours
Min Dose: 3 mL (75 mg) po every 6 hours
Max Dose: 6 mL (150 mg) po every 6 hours

Adults:
Usual dose is 500 mg po every 6 hours

⚠️ This tool is for information purposes only...

Consult a healthcare provider before administering.

Frequently Asked Questions (FAQ)

1. What is Ampicillin used for?

Ampicillin treats bacterial infections such as respiratory tract infections, urinary tract infections, and meningitis.

2. How often can Ampicillin be given?

Dosing is QID (4 times daily, every 6 hours) for 7–10 days or as prescribed.

3. Can this be used for infants under 3 months?

Consult a doctor, as dosing for infants under 3 months may differ (e.g., caution or lower doses).

4. What if weight is in pounds?

Select 'lb,' and the calculator converts to kg automatically.

5. What’s the maximum daily dose for pediatrics?

Up to 100 mg/kg/day PO QID, with a maximum of 2 g/day (2000 mg/day).