ZIPSOR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ZIPSOR (ZIPSOR).
Celecoxib is a nonsteroidal anti-inflammatory drug (NSAID) that selectively inhibits cyclooxygenase-2 (COX-2), reducing prostaglandin synthesis involved in inflammation, pain, and fever. It has no significant inhibition of COX-1 at therapeutic doses.
| Metabolism | Celecoxib is metabolized primarily by cytochrome P450 (CYP) 2C9 in the liver to inactive metabolites (hydroxycelecoxib and carboxycelecoxib). Minor metabolism via CYP3A4. |
| Excretion | Renal: ~60% unchanged; biliary/fecal: ~30% as metabolites; remainder as glucuronide conjugates |
| Half-life | 2-4 hours (terminal); clinical context: short half-life necessitates frequent dosing for sustained relief; prolonged in hepatic impairment |
| Protein binding | >99% bound to albumin |
| Volume of Distribution | 0.1-0.2 L/kg; low Vd indicates limited tissue distribution, primarily in plasma and extracellular fluid |
| Bioavailability | Oral: ~80-100% (immediate-release); rectal: ~70-90%; intramuscular: ~100% |
| Onset of Action | Oral (immediate-release): ~30 minutes; peak effect: 1-2 hours |
| Duration of Action | 4-6 hours (immediate-release); clinical note: duration correlates with analgesic effect; extended-release formulations provide up to 12-24 hours |
| Molecular Weight | 318.13 |
50 mg orally three times daily
| Dosage form | CAPSULE |
| Renal impairment | eGFR 30-59 mL/min: 25 mg three times daily; eGFR <30 mL/min: not recommended |
| Liver impairment | Child-Pugh class A: no adjustment; Child-Pugh class B: 25 mg three times daily; Child-Pugh class C: not recommended |
| Pediatric use | Not established; contraindicated in children less than 2 years of age |
| Geriatric use | No specific adjustment; use lowest effective dose; consider increased sensitivity to adverse effects |
| 1st trimester | Avoid use due to potential teratogenic effects; limited human data, but animal studies suggest risk. |
| 2nd trimester | Use only if clearly needed; NSAIDs may cause oligohydramnios and premature ductus arteriosus closure. |
| 3rd trimester | Contraindicated due to risk of premature closure of ductus arteriosus and oligohydramnios. |
Clinical note
Comprehensive clinical and safety monograph for ZIPSOR (ZIPSOR).
| Placental transfer | Diclofenac crosses the placenta; fetal serum levels are about 20-40% of maternal levels. |
| Breastfeeding | Diclofenac (ZIPSOR) is excreted into breast milk in low amounts. Consider risk vs benefit; avoid in nursing mothers with pre-existing renal impairment or bleeding disorders. |
| Lactation Rating |
■ FDA Black Box Warning
Cardiovascular risk: NSAIDs increase the risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, which can be fatal. This risk may increase with duration of use and in patients with cardiovascular risk factors. ZIPSOR is contraindicated for the treatment of perioperative pain in coronary artery bypass graft (CABG) surgery.
| Serious Effects |
Absolute contraindication: use in setting of coronary artery bypass graft (CABG) surgeryAbsolute contraindication: patients with active peptic ulcer disease or gastrointestinal bleedingAbsolute contraindication: patients with known hypersensitivity to diclofenac or other NSAIDsAbsolute contraindication: patients with aspirin-sensitive asthmaAbsolute contraindication: patients with severe, uncontrolled heart failureAbsolute contraindication: patients with advanced renal disease (unless undergoing dialysis)Absolute contraindication: patients with history of severe allergic reaction to NSAIDs
| Precautions | Cardiovascular thrombotic events: Use lowest effective dose for shortest duration., Gastrointestinal effects: Risk of serious GI adverse events including bleeding, ulceration, and perforation., Hypertension: NSAIDs can lead to new-onset hypertension or worsening of pre-existing hypertension., Heart failure: Fluid retention and edema may occur., Renal effects: Monitor renal function in patients with pre-existing renal disease, heart failure, or on diuretics., Anaphylactoid reactions: Reported in patients with aspirin sensitivity., Serious skin reactions: Including exfoliative dermatitis, Stevens-Johnson syndrome, and toxic epidermal necrolysis., Pregnancy: Avoid use during late pregnancy (third trimester) due to risk of premature closure of ductus arteriosus., Hematologic effects: May prolong bleeding time; monitor for signs of bleeding. |
Loading safety data…
| L2 (Probably Compatible) |
| Teratogenic Risk | ZIPSOR (diclofenac potassium) is classified as FDA Pregnancy Category C prior to 30 weeks gestation and Category D starting at 30 weeks. First trimester: Risk of spontaneous abortion and congenital malformations (cardiac, orofacial clefts) based on epidemiological studies. Second trimester: Possible oligohydramnios and fetal renal dysfunction. Third trimester: Premature closure of ductus arteriosus, oligohydramnios, necrotizing enterocolitis, intracranial hemorrhage, and renal impairment. |
| Fetal Monitoring | Monitor fetal ultrasound for oligohydramnios and ductus arteriosus patency after 30 weeks gestation. Evaluate maternal renal function, bleeding time, and blood pressure routinely. Assess for signs of fetal distress and growth restriction. |
| Fertility Effects | Diclofenac may impair female fertility by inhibiting prostaglandin synthesis, potentially leading to luteinized unruptured follicle syndrome and reversible delayed ovulation. Effects are reversible upon discontinuation. Male fertility impact is unclear. |
| Food/Dietary | Avoid alcohol; may increase risk of gastrointestinal bleeding. No specific food interactions, but high-fat meals may delay absorption. |
| Clinical Pearls | ZIPSOR is an oral diclofenac potassium formulation with enhanced absorption; take on empty stomach for fastest pain relief. Avoid in patients with significant cardiovascular disease or renal impairment. Monitor hepatic enzymes and renal function with prolonged use. |
| Patient Advice | Take with food or milk to reduce stomach upset, but for fastest effect, take on an empty stomach. · Do not take more than 3 packets (150 mg) per day. · Avoid alcohol while taking this medication. · Notify your doctor if you experience black stools, chest pain, shortness of breath, or signs of liver damage (yellow skin, dark urine). · May cause dizziness; avoid driving if affected. |