Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
Cefazolin vs ACTIQ
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Cefazolin is a first-generation cephalosporin antibiotic that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), thereby inhibiting transpeptidation and disrupting peptidoglycan cross-linking. This leads to cell lysis and death primarily in susceptible gram-positive bacteria.
Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.
Perioperative prophylaxis (surgical prophylaxis),Respiratory tract infections,Urinary tract infections,Skin and soft tissue infections,Biliary tract infections,Bone and joint infections,Genital infections,Septicemia,Endocarditis (off-label)
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
1-2 g IV/IM every 6-8 hours; maximum 12 g/day.
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.
1.8 hours in normal renal function; extends to 30–70 hours in end-stage renal disease (Cr Cl <10 m L/min).
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.
Cefazolin undergoes minimal hepatic metabolism; it is primarily excreted unchanged in the urine via glomerular filtration and tubular secretion. The drug is not significantly metabolized by the liver.
Primarily hepatic via CYP3A4 to inactive metabolites (norfentanyl, despropionylfentanyl, hydroxyfentanyl) and other metabolites; <7% excreted unchanged in urine.
Renal: 80–90% unchanged via glomerular filtration and tubular secretion; biliary: <1%; fecal: negligible.
Primarily renal as metabolites (about 75% as metabolites, <10% unchanged). Fecal excretion accounts for <9%. Biliary excretion is minor.
80% bound to albumin.
Fentanyl is 80–85% bound to plasma proteins (primarily albumin and α1-acid glycoprotein).
0.12–0.14 L/kg; approximates extracellular fluid volume, indicating low tissue penetration.
Approximately 4 L/kg (range 3–6 L/kg); large Vd indicates extensive tissue distribution and redistribution contributing to short duration.
Intramuscular: 100% (complete absorption).
Oral transmucosal: 50% (range 47–54%) relative to IV; variable and enhanced by rapid absorption through buccal mucosa.
Cr Cl >55 m L/min: no adjustment; Cr Cl 35-54 m L/min: 1-2 g every 8 hours; Cr Cl 11-34 m L/min: 500 mg-1 g every 12 hours; Cr Cl ≤10 m L/min: 500 mg-1 g every 24-48 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 dosage adjustment required for hepatic 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.
50-100 mg/kg/day IV/IM divided every 8 hours; severe infections: 100 mg/kg/day divided every 6-8 hours.
Not approved for pediatric use; safety and efficacy not established in patients under 16 years.
No specific adjustment based solely on age; dose adjustment based on renal function per Cr Cl.
Initiate at 100 mcg transmucosally; titrate slowly due to increased sensitivity and risk of respiratory depression. Monitor for adverse effects.
No FDA black box warning.
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) may occur; cross-allergenicity among cephalosporins and penicillins is possible.,Clostridioides difficile-associated diarrhea (CDAD) can occur with antibiotic use.,Dosage adjustment required in patients with renal impairment due to predominantly renal elimination.,Prolonged use may result in overgrowth of nonsusceptible organisms (e.g., Candida, Pseudomonas).,Seizures may occur with high doses, especially in patients with renal impairment.
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.
Known hypersensitivity to cefazolin or any cephalosporin antibiotic,Immediate-type hypersensitivity reaction to penicillins (relative caution due to potential cross-allergenicity)
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 significant food interactions. Alcohol should be avoided during treatment and for at least 72 hours after last dose due to potential disulfiram-like reaction (nausea, vomiting, flushing).
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.
Cefazolin is classified as FDA Pregnancy Category B. Animal studies have not demonstrated fetal risk, and adequate, well-controlled studies in pregnant women are lacking. Generally considered safe throughout pregnancy; no known teratogenic effects in the first trimester. 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.
Cefazolin is excreted into breast milk in low concentrations (M/P ratio approximately 0.02–0.05). It is considered compatible with breastfeeding; potential for infant gut flora alteration but unlikely to cause adverse effects. Use caution in neonates with hyperbilirubinemia or glucose-6-phosphate dehydrogenase deficiency.
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.
Pregnancy increases volume of distribution and renal clearance, potentially lowering serum concentrations. Standard dosing (1–2 g every 8 hours for most infections) is generally adequate; for serious infections, consider higher doses (up to 12 g/day) or more frequent intervals (every 6 hours) in the third trimester. Adjust based on therapeutic response and renal function.
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.
Cefazolin is a first-generation cephalosporin with a short half-life; requires dose adjustment in renal impairment. Watch for cross-allergenicity in penicillin-allergic patients (approx. 10% risk). Administer parenterally only; no oral formulation available. Common surgical prophylaxis antibiotic due to good coverage of skin flora.
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.
This medication is given by injection or IV, not by mouth.,Report any signs of allergic reaction: rash, hives, itching, difficulty breathing.,May cause diarrhea; notify your doctor if severe or persistent.,Avoid alcohol while taking this medication to prevent disulfiram-like reaction.,Complete the full course as prescribed even if you feel better.
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.
"Phenprocoumon may increase the anticoagulant activities of Cefazolin."
"Warfarin may increase the anticoagulant activities of Cefazolin."
"The protein binding of Cefazolin can be decreased when combined with Phenytoin."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about Cefazolin vs ACTIQ, answered by our medical review team.
Cefazolin is a Cephalosporin Antibiotic that works by Cefazolin is a first-generation cephalosporin antibiotic that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), thereby inhibiting transpeptidation and disrupting peptidoglycan cross-linking. This leads to cell lysis and death primarily in susceptible gram-positive bacteria.. 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 Cefazolin 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 Cefazolin is: 1-2 g IV/IM every 6-8 hours; maximum 12 g/day.. 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 Cefazolin 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. Cefazolin is classified as Category A/B. Cefazolin is classified as FDA Pregnancy Category B. Animal studies have not demonstrated fetal risk, and adequate, well-controlled studies in pregnant women are lacking. Generally. 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.