Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CEFZIL vs ACTIQ
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Cefprozil inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), inhibiting peptidoglycan cross-linking.
Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.
Pharyngitis/tonsillitis (Streptococcus pyogenes),Otitis media (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis),Acute sinusitis,Acute bacterial exacerbation of chronic bronchitis,Skin and skin structure infections (uncomplicated)
Management of breakthrough pain in cancer patients aged 16 and older who are already receiving and tolerant to opioid therapy for their underlying persistent cancer pain
500 mg orally twice daily for 10 days; for uncomplicated skin infections, 250 mg twice daily or 500 mg once daily.
200 mcg transmucosally, titrated upward as needed; initial dose for opioid-tolerant patients is 200 mcg, with additional doses possible after 15 minutes if needed. Maximum 4 doses per episode. At least 4 hours between episodes.
1.2-1.5 hours in healthy adults; prolonged in renal impairment (e.g., up to 6-8 hours in severe renal failure)
Terminal half-life 0.83–2 hours (mean 1.3 h) in adults; note that context: transmucosal absorption leads to rapid onset but short duration; half-life is not correlated with clinical effect due to oral transmucosal route and rapid redistribution.
Cefprozil is not extensively metabolized; approximately 60% of the dose is excreted unchanged in the urine. Renal excretion via tubular secretion and glomerular filtration.
Primarily hepatic via CYP3A4 to inactive metabolites (norfentanyl, despropionylfentanyl, hydroxyfentanyl) and other metabolites; <7% excreted unchanged in urine.
Renal: 80-91% unchanged in urine; biliary/fecal: minimal (<5%)
Primarily renal as metabolites (about 75% as metabolites, <10% unchanged). Fecal excretion accounts for <9%. Biliary excretion is minor.
65-80% bound to plasma proteins (mainly albumin)
Fentanyl is 80–85% bound to plasma proteins (primarily albumin and α1-acid glycoprotein).
0.23-0.35 L/kg; distributes well into body fluids and tissues including skin, soft tissue, and respiratory tract
Approximately 4 L/kg (range 3–6 L/kg); large Vd indicates extensive tissue distribution and redistribution contributing to short duration.
Oral: 90-95%
Oral transmucosal: 50% (range 47–54%) relative to IV; variable and enhanced by rapid absorption through buccal mucosa.
Cr Cl 30-49 m L/min: 250 mg twice daily; Cr Cl 10-29 m L/min: 250 mg once daily; Cr Cl <10 m L/min: 250 mg every 48 hours.
No specific GFR-based dose adjustment recommended; use with caution in severe renal impairment (Cr Cl < 30 m L/min) and consider dose reduction due to potential accumulation.
No dose adjustment required for mild to moderate hepatic impairment; not studied in severe impairment.
Child-Pugh Class A/B: No adjustment. Child-Pugh Class C: Reduce initial dose to 100 mcg and titrate slowly; monitor closely for prolonged effects.
6 months to 12 years: 30 mg/kg/day divided twice daily (max 1 g/day); for pharyngitis/tonsillitis: 20 mg/kg/day divided twice daily (max 500 mg/day).
Not approved for pediatric use; safety and efficacy not established in patients under 16 years.
Adjust dose based on renal function; no specific geriatric dose adjustments other than renal considerations.
Initiate at 100 mcg transmucosally; titrate slowly due to increased sensitivity and risk of respiratory depression. Monitor for adverse effects.
None.
Risk of respiratory depression, addiction, abuse, and misuse; accidental ingestion can be fatal; concomitant use with benzodiazepines or CNS depressants may cause profound sedation, respiratory depression, coma, and death; not for use in opioid non-tolerant patients; risk of neonatal opioid withdrawal syndrome with prolonged use during pregnancy; serious, life-threatening, or fatal respiratory depression may occur even at recommended doses.
Hypersensitivity reactions (including anaphylaxis) in penicillin-allergic patients,Clostridium difficile-associated diarrhea (CDAD),Seizures with high doses or renal impairment,Hemolytic anemia (rare),Prolonged prothrombin time (rare)
Risk of respiratory depression; addiction, abuse, and misuse; interactions with CNS depressants; serotonin syndrome; adrenal insufficiency; severe hypotension; seizures; withdrawal; use in patients with head injuries, increased intracranial pressure, biliary tract disease, pancreatitis; risk of choking with lozenge; oral mucosal irritation; dental caries; hypokalemia; hyponatremia; use in elderly, cachectic, or debilitated patients.
Hypersensitivity to cefprozil or other cephalosporins,Immediate-type hypersensitivity to penicillins (cross-reactivity risk)
Significant respiratory depression; acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment; known or suspected paralytic ileus; hypersensitivity to fentanyl or any component; opioid non-tolerant patients; management of acute or postoperative pain including headache/migraine, dental pain, or emergency department use.
No clinically significant food interactions. High-fat meals may slightly delay absorption but do not affect overall absorption extent. Avoid alcohol during therapy as it may increase risk of disulfiram-like reaction (rare with cephalosporins).
No significant food interactions. Grapefruit juice may increase fentanyl levels, but specific studies with ACTIQ are lacking. Avoid alcohol, as it may increase sedation and respiratory depression risk.
FDA Pregnancy Category B. Animal studies have not demonstrated fetal risk, but no adequate human studies. Risk cannot be ruled out. First trimester: No reported teratogenicity in animal studies; clinical data insufficient. Second/third trimester: No known risk; use only if clearly needed.
FDA Pregnancy Category C. First trimester: limited human data; animal studies show increased resorptions and fetal growth restriction. Second/third trimester: chronic use may cause neonatal opioid withdrawal syndrome; avoid use during labor due to risk of neonatal respiratory depression.
Cefprozil (CEFZIL) is excreted in human milk in low amounts. Milk-to-plasma ratio is approximately 0.3. Considered compatible with breastfeeding; however, monitor infant for potential gastrointestinal effects.
Excreted in breast milk; M/P ratio not established. Limited data suggest low levels, but risk of infant sedation and respiratory depression. Avoid use while breastfeeding unless potential benefit outweighs risk.
No dose adjustment routinely required. Physiologic changes in pregnancy (increased renal clearance, volume of distribution) may require higher doses for severe infections, but data insufficient to recommend specific adjustments. Use standard adult dosing unless renal impairment.
Due to increased plasma volume and hepatic metabolism in pregnancy, dose requirements may increase; adjust based on clinical response and tolerance. Avoid use during labor and delivery due to risk of neonatal respiratory depression; short-term use preferred.
CEFZIL (cefprozil) is a second-generation cephalosporin with activity against Gram-positive cocci (including Streptococcus pyogenes, Streptococcus pneumoniae, and methicillin-susceptible Staphylococcus aureus) and some Gram-negative bacteria (Haemophilus influenzae, Moraxella catarrhalis, Escherichia coli). It has a longer half-life (1.3 hours) compared to cephalexin, allowing twice-daily dosing. It is FDA-approved for acute sinusitis, pharyngitis/tonsillitis, otitis media, acute bacterial exacerbation of chronic bronchitis, secondary bacterial infection of acute bronchitis, and uncomplicated skin and skin structure infections. Note that it is not reliable against penicillin-resistant S. pneumoniae or beta-lactamase-producing H. influenzae (though it is more stable than first-generation agents). In penicillin-allergic patients, cross-reactivity risk is low but not zero (avoid if immediate-type hypersensitivity to penicillin). Dose adjustment required for creatinine clearance <30 m L/min: give standard dose every 12 hours for first dose, then 50% of standard dose every 12 hours. Available as 250 mg and 500 mg tablets and as an oral suspension (125 mg/5 m L or 250 mg/5 m L). Refrigerate suspension after reconstitution; discard after 14 days.
ACTIQ is a transmucosal immediate-release fentanyl formulation indicated for breakthrough cancer pain in opioid-tolerant patients. Initiate with the lowest strength (200 mcg) and titrate upward. Avoid use in opioid-naive patients due to risk of fatal respiratory depression. Place the unit between cheek and lower gum, not sublingually. Instruct patient not to bite or suck the unit. Monitor for sedation and respiratory depression. Multiple units may be used per episode if needed, but wait at least 4 hours before next episode. Dispose of partially used units by flushing down toilet.
Take this medication exactly as prescribed by your doctor, usually every 12 hours.,You may take this medication with or without food; however, taking with food may help reduce stomach upset.,Complete the full course of therapy, even if you feel better, to reduce the risk of antibiotic resistance.,Shake the oral suspension well before each dose. Use a proper measuring spoon or dosing syringe to ensure accurate dose.,Store the oral suspension in the refrigerator (not freezer) and discard any unused portion after 14 days.,Notify your doctor if you develop diarrhea, especially if it is watery or bloody; do not use anti-diarrhea medications without consulting your doctor.,Seek immediate medical attention if you experience signs of an allergic reaction: rash, hives, itching, difficulty breathing, tightness in chest, swelling of face/mouth/tongue.,Inform your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
Only use ACTIQ if you are already taking regular around-the-clock opioid pain medicine and are tolerant to opioids.,Do not use ACTIQ for short-term pain like after surgery, headache, or dental pain.,Place the unit in your cheek pouch, not under your tongue. Do not chew or suck it.,If you need more than 4 units per day, contact your doctor as your dose may need adjustment.,Store ACTIQ in a safe place away from children, as accidental ingestion can be fatal.,Dispose of unused or partially used units by flushing them down the toilet.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about CEFZIL vs ACTIQ, answered by our medical review team.
CEFZIL is a Cephalosporin Antibiotic that works by Cefprozil inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), inhibiting peptidoglycan cross-linking.. ACTIQ is a Opioid Analgesic that works by Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CEFZIL and ACTIQ depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of CEFZIL is: 500 mg orally twice daily for 10 days; for uncomplicated skin infections, 250 mg twice daily or 500 mg once daily.. The standard adult dose of ACTIQ is: 200 mcg transmucosally, titrated upward as needed; initial dose for opioid-tolerant patients is 200 mcg, with additional doses possible after 15 minutes if needed. Maximum 4 doses per episode. At least 4 hours between episodes.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between CEFZIL and ACTIQ in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. CEFZIL is classified as Category C. FDA Pregnancy Category B. Animal studies have not demonstrated fetal risk, but no adequate human studies. Risk cannot be ruled out. First trimester: No reported teratogenicity in a. ACTIQ is classified as Category C. FDA Pregnancy Category C. First trimester: limited human data; animal studies show increased resorptions and fetal growth restriction. Second/third trimester: chronic use may cause. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.