Cefixime Syrup Dose Calculator for Children
Use this cefixime syrup dose calculator to convert mg/kg targets into exact mL doses for cefixime 100 mg/5 mL suspension, then confirm whether the plan is once daily or split.
Usual oral dose for children 6 months and older: 8 mg/kg per day, given once daily or as 4 mg/kg every 12 hours (max 400 mg per day). Enter weight for the mL on your bottle; give the dose your child's prescriber ordered.
dose calculator basics
Cefixime pediatric dose calculator details
Use this Cefixime calculator as the fast parent page for weight-based dose checks, mL conversion, common strengths, and the practical safety steps that generic calculator sites often skip.
Formula
mL per dose = (child weight in kg x prescribed mg/kg/day / doses per day) / medication concentration in mg per mL.
Worked example
For a 20 kg child using 8 mg/kg/day divided 1 time daily with 100 mg/5 mL, calculate the daily mg target, divide by the schedule, then convert that mg amount into mL for the selected product.
Safety checks before using the result
- Use the exact product strength in hand before measuring the dose.
- Confirm maximum dose, age limits, and indication-specific cautions when they apply.
- Escalate urgent symptoms or medication reactions instead of repeating doses from calculator output alone.
Practical dosing guide
Before you measure the dose
Use this page when you need to turn a cefixime prescription into a clear syrup, chewable, or capsule plan for a child.
- 100 mg/5 mL suspension
- The most common first step is matching the prescribed cefixime amount to the exact bottle strength so the 100 mg/5 mL suspension converts into the right mL dose.
- Once daily versus split dosing
- Many cefixime plans are given once daily, while some are divided.
- Suprax bottle check
- Families often search for Suprax by name.
Cefixime pediatric medication summary
Cefixime is an oral third-generation cephalosporin used selectively in pediatrics. Use this route when the main question is turning a prescribed cefixime syrup plan into the right mL dose, especially for common 100 mg/5 mL Suprax-style suspension workflows.
Dose once daily (8 mg/kg/day) or divided twice daily based on tolerance and indication.
Reserve for scenarios with suspected beta-lactamase–producing organisms or when adherence favors once-daily therapy.
Cefixime indications and common pediatric uses
Cefixime is an oral third-generation cephalosporin reserved for upper respiratory infections and UTIs when first-line therapies fail or cannot be used.
Acute otitis media
Acute otitis media: Use when amoxicillin/clavulanate is not tolerated or nasopharyngeal beta-lactamase producers are likely. Treat ear infections with the suspension or chewable tablets; the label says not to use regular tablets or capsules for otitis media because they give lower blood levels.
Acute bacterial rhinosinusitis
Acute bacterial rhinosinusitis: Reserve for penicillin allergy (non-IgE) or after amoxicillin/clavulanate failure.
Group A streptococcal pharyngitis
Group A streptococcal pharyngitis: Only when penicillin or amoxicillin cannot be used; ensure negative immediate penicillin allergy history to reduce cross-reactivity concerns.
Uncomplicated urinary tract infection (culture-directed)
Uncomplicated urinary tract infection (culture-directed): Not first-line; prefer nitrofurantoin or TMP-SMX when susceptible.
Gonococcal urethritis/cervicitis (adolescents)
Gonococcal urethritis/cervicitis (adolescents): 800 mg PO once (CDC 2021) only when ceftriaxone is unavailable; test of cure is recommended; requires public health consultation.
How to give Cefixime
- Cefixime’s once-daily option improves adherence, but accurate measuring and shake-before-use instructions are key.
- Shake the suspension hard for 10–15 seconds before each dose, measure with a marked syringe, and give with breakfast (once daily) or breakfast/dinner (BID). Swallow regular tablets and capsules whole with water; only chewable tablets may be chewed. Always separate cefixime from iron-containing supplements or aluminum/magnesium antacids by at least 2 hours.
- Post a dosing chart on the fridge, set phone alarms, and keep the syringe beside the bottle. Rinse the measuring device after every dose, store the suspension away from heat/light, and remind caregivers not to share leftover antibiotic with siblings.
Cefixime side effects, contraindications, and interactions
Cefixime is generally well tolerated, with gastrointestinal upset and rash as the most common adverse effects. Families should use clear stop/escalation rules for allergy signs, severe diarrhea, persistent vomiting, or dehydration concerns.
Common side effects
- Call immediately for hives, swelling of the face or throat, or trouble breathing—signs of possible anaphylaxis.
- Monitor stool patterns. Watery diarrhea, blood in stool, or stomach cramps may indicate C. difficile colitis.
- Maintain hydration and offer probiotics or yogurt if tolerated to reduce antibiotic-associated diarrhea.
Safety checks
- Immediate hypersensitivity to cefixime or other cephalosporins
- History of severe cutaneous adverse reaction (Stevens–Johnson syndrome, toxic epidermal necrolysis) to any beta-lactam
- Severe IgE-mediated penicillin allergy
- Renal insufficiency (creatinine clearance <60 mL/min/1.73 m²)
- Documented history of C. difficile infection after antibiotics
- History of cephalosporin-associated serum sickness-like reaction
Drug interactions
- Review the full medication list with a clinician or pharmacist before combining therapies.
Cefixime mechanism and clinical pearls
Cefixime is an oral third-generation cephalosporin that kills bacteria by inhibiting cell wall synthesis. It binds penicillin-binding proteins (PBPs), particularly those involved in gram-negative cell division, and blocks peptidoglycan cross-linking, leading to bacterial lysis. Cefixime is more stable to many beta-lactamases produced by respiratory pathogens such as Haemophilus influenzae and Moraxella catarrhalis compared with earlier cephalosporins. Its half-life supports once-daily dosing, which improves adherence in children. Activity remains time dependent, so maintaining adequate exposure across the dosing interval is critical, especially in severe infections or in patients with renal impairment.
Use cefixime after amoxicillin or amoxicillin-clavulanate failure or intolerance. Document why first-line therapy is unsuitable to support stewardship metrics.
Review current local susceptibility trends for likely pathogens before defaulting to cefixime as empiric escalation.
A single morning dose with breakfast maintains therapeutic levels and improves completion compared with multiple daily cephalosporins.
Cefixime can trigger false-positive Clinitest results; use enzymatic assays if glucose monitoring is necessary.
Frequently asked questions about Cefixime
Use the child’s weight and the prescribed mg/kg target in the calculator, then match that result to the syrup strength in hand. This is the safest way to turn a cefixime plan into an exact mL dose.
Use your clinician's prescribed mg/kg target and your child’s current weight to generate an mL dose for the bottle concentration. Recheck dose whenever weight or concentration changes.
Yes. A light meal or snack can lessen stomach upset without affecting absorption. Shake the suspension well and measure each dose with an oral syringe.
Give it as soon as you remember unless the next dose is due within 6 hours. Do not double up—resume the regular schedule and call if multiple doses are missed.
It treats susceptible gram-negative bacteria but does not cover Pseudomonas or Enterococcus. Culture-guided therapy is important; follow-up is needed if symptoms recur.
Magnesium- or aluminum-containing antacids can reduce absorption and should be separated by at least 2 hours. Notify your clinician about anticoagulants or other antibiotics, as monitoring may be needed.
Sources reviewed for Cefixime
Suprax (Cefixime) Prescribing Information
DailyMed
SourceCefixime Tablets and Oral Suspension
DailyMed
SourceAAP Red Book: Beta-lactam Allergy
American Academy of Pediatrics
SourceIDSA Guidance for Pediatric C. difficile
Clinical Infectious Diseases
Sourcedailymed-suprax-cefixime-655a59ba-2025
medlineplus-cefixime-2025