Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CEQUA vs AZATHIOPRINE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Immunosuppressant; binds to cyclophilin D in mitochondria, inhibiting opening of mitochondrial permeability transition pore (m PTP), which reduces T-lymphocyte activation and cytokine release. Also forms complex with cyclophilin A to inhibit calcineurin, suppressing IL-2 production and T-cell proliferation.
Azathioprine is a purine analog that inhibits purine nucleotide synthesis, thereby suppressing DNA replication and cell proliferation. It is converted to 6-mercaptopurine, which acts as a purine antagonist, inhibiting de novo purine synthesis and interfering with RNA and DNA synthesis, particularly in rapidly dividing cells such as T-lymphocytes.
Dry eye disease due to keratoconjunctivitis sicca (KCS),Post-keratoplasty dry eye,Dry eye in Sjögren's syndrome
Renal transplant rejection prophylaxis (FDA),Rheumatoid arthritis (FDA),Off-label: autoimmune hepatitis, systemic lupus erythematosus, inflammatory bowel disease (Crohn's disease, ulcerative colitis), pemphigus, myasthenia gravis, dermatomyositis/polymyositis,Off-label: myelodysplastic syndrome, refractory immune thrombocytopenic purpura, atopic dermatitis, Behçet's syndrome
Instill one drop of 0.09% ophthalmic solution in each eye twice daily, approximately 12 hours apart.
1.5 to 2.5 mg/kg orally once daily; typical adult dose 50-150 mg/day orally. Intravenous dose is 3-5 mg/kg/day as a slow infusion over 30-60 minutes.
Terminal elimination half-life is approximately 8.4 hours (range 6-10 hours) in healthy adults; prolonged in hepatic impairment and pediatric patients.
Terminal elimination half-life of azathioprine is approximately 2–5 hours; its active metabolite 6-mercaptopurine has a half-life of 1–2 hours, but 6-thioguanine nucleotides accumulate in red blood cells with a half-life of several days, correlating with myelosuppression.
Hepatic via CYP3A4 and CYP3A5; also undergoes fecal elimination with enterohepatic recirculation.
Azathioprine is metabolized by xanthine oxidase (XO) and thiopurine methyltransferase (TPMT) to active (6-mercaptopurine) and inactive metabolites. 6-Mercaptopurine is further metabolized by XO to 6-thiouric acid and by TPMT to 6-methylmercaptopurine. Genetic deficiency of TPMT increases risk of toxicity.
Primarily fecal (90%) with minor renal excretion (<1% unchanged drug). Biliary excretion is the major route for elimination of cyclosporine metabolites.
Renal (approximately 2% as unchanged drug, 30% as 6-thiouric acid and other metabolites); biliary/fecal (minor, <10% as metabolites).
90-98% bound primarily to lipoproteins (HDL, LDL) and to a lesser extent albumin and globulins.
Approximately 30% bound, primarily to albumin.
4-8 L/kg, indicating extensive distribution into tissues (e.g., fat, liver, kidneys).
0.8–1.0 L/kg, indicating distribution into total body water; extensive distribution into tissues including liver and erythrocytes.
Ophthalmic emulsion: systemic bioavailability is negligible (<0.1%) due to low absorption from the eye.
Oral bioavailability of azathioprine is 60–80% (mean 70%) with interindividual variability; absorption may be reduced by food.
No dosage adjustment required for renal impairment.
GFR >50 m L/min: no adjustment. GFR 10-50 m L/min: administer 75% of normal dose. GFR <10 m L/min: administer 50% of normal dose. Hemodialysis: administer 50% of normal dose after dialysis.
No dosage adjustment required for hepatic impairment.
Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 25-50%. Child-Pugh Class C: contraindicated or use with extreme caution; reduce dose by at least 50%.
Safety and efficacy in pediatric patients have not been established.
1.5 to 2.5 mg/kg orally once daily; maximum 150 mg/day. For inflammatory bowel disease: 2-3 mg/kg/day. Intravenous: 3-5 mg/kg/day as a slow infusion.
No specific dosage adjustment recommended; use with caution due to potential for increased systemic exposure.
Initiate at lower end of dosing range (1.5 mg/kg/day) due to potential for decreased renal and hepatic function; monitor renal function and hematologic parameters closely.
Increased risk of infection and lymphoproliferative disorders including post-transplant lymphoproliferative disorder (PTLD).
Malignancy: Patients receiving immunosuppressive therapy including azathioprine have an increased risk of developing lymphoma and other malignancies, particularly skin cancers. The risk is related to the duration and intensity of immunosuppression. Hematologic toxicity: Severe leukopenia, thrombocytopenia, and anemia, which may be dose-related, can occur. Regular monitoring of blood counts is required. Hepatotoxicity: Hepatotoxicity, including fatal liver injury, has been reported, particularly at high doses.
Increased susceptibility to infections,Potential for lymphoproliferative disorders and other malignancies,May cause renal impairment, hypertension, hyperkalemia, and hyperuricemia,Monitor blood cyclosporine levels to avoid toxicity,Avoid concurrent use of live vaccines,Caution with other nephrotoxic drugs
Hematologic monitoring: regular CBCs; Increased risk of infection; Hepatotoxicity; Pancreatitis; Carcinogenicity (lymphoma, skin cancer); TPMT deficiency increases myelotoxicity; Vaccination (live vaccines contraindicated); Renal and hepatic impairment; Drug interactions: allopurinol (reduce dose by 75%), ACE inhibitors (anemia), warfarin (anticoagulant effect decreased).
Hypersensitivity to cyclosporine or any component,Uncontrolled hypertension,Severe renal impairment (except in transplant setting),Active infections,Concurrent use with PUVA or UVB therapy
Hypersensitivity to azathioprine or 6-mercaptopurine; Pregnancy (unless benefit outweighs risk) - Category D; Lactation; Patients with TPMT deficiency (increased risk of severe myelotoxicity); Severely depressed bone marrow function; Active infections; Concurrent use of live vaccines; Pre-existing malignancy (except in organ transplantation context).
No significant food interactions reported for ophthalmic cyclosporine. However, patients should avoid touching the dropper tip to food surfaces. No dietary restrictions are necessary.
No known significant food interactions. Avoid grapefruit juice? (No interaction reported). Maintain consistent diet; no specific restrictions. Limit alcohol due to hepatotoxicity risk.
CEQUA (cyclosporine ophthalmic solution) is classified as Pregnancy Category C. Animal studies have shown embryotoxic and fetotoxic effects at doses 0.2-0.8 times the human ocular dose. There are no adequate and well-controlled studies in pregnant women. Use only if potential benefit justifies potential risk to the fetus. First trimester: limited data, theoretical risk of immunosuppression. Second and third trimesters: no specific human data, but systemic cyclosporine is associated with increased risk of prematurity and low birth weight.
Azathioprine is pregnancy category D. First trimester: increased risk of congenital anomalies including ventricular septal defects, limb defects, and esophageal atresia. Second and third trimesters: risk of intrauterine growth restriction, preterm birth, and neonatal immunosuppression (leukopenia, thrombocytopenia). Use only if benefit outweighs risk.
Systemic cyclosporine is excreted in human milk. The M/P ratio is approximately 0.3-0.6. However, CEQUA is an ophthalmic formulation with minimal systemic absorption. Unknown whether topically applied cyclosporine is excreted in milk. Use caution, considering the importance of the drug to the mother. Breastfeeding infants should be monitored for potential adverse effects such as immune suppression.
Azathioprine is excreted into breast milk in low concentrations. M/P ratio is approximately 0.7. Nursing infants of mothers on azathioprine have not shown adverse effects; however, theoretical risk of immunosuppression exists. Caution is advised; monitor infant for increased infections.
No specific dosing adjustments are recommended for CEQUA in pregnancy due to its local administration and minimal systemic absorption. Pharmacokinetic changes in pregnancy (e.g., increased volume of distribution, altered protein binding) are unlikely to affect ophthalmic drug levels. No dose adjustment required.
Pharmacokinetic changes in pregnancy include increased clearance and decreased absorption. Dose may need adjustment to maintain therapeutic efficacy. Close monitoring of disease activity and drug levels (6-thioguanine nucleotide levels) is recommended. No standard dose adjustment; individualization required.
CEQUA (cyclosporine ophthalmic solution 0.09%) is a calcineurin inhibitor immunosuppressant indicated for keratoconjunctivitis sicca (dry eye disease). It increases tear production by inhibiting T-cell activation. Important: CEQUA requires no refrigeration (unlike Restasis), and the vehicle contains no preservatives. Use with caution in patients with active ocular infections; do not administer while wearing contact lenses. Onset of effect may take 2-4 weeks; maximum benefit may require 6 months. Contraindicated in patients with known hypersensitivity to cyclosporine.
Monitor CBC and LFTs weekly for first month, then biweekly for 2 months, then monthly. TPMT genotype testing before initiation. Avoid concurrent allopurinol unless dose reduced to 25% of original. Use with caution in renal impairment. May cause hepatotoxicity, pancreatitis, or lymphoproliferative disorders.
CEQUA is a prescription eye drop used to increase tear production in dry eye disease.,Instill one drop in each eye twice daily, about 12 hours apart.,Remove contact lenses before use; wait at least 15 minutes before reinserting.,Do not touch the dropper tip to any surface to avoid contamination.,CEQUA comes in a single-use vial; use immediately after opening and discard any remaining solution.,Temporary blurred vision may occur after instillation; wait until vision clears before driving.,Report any eye pain, vision changes, or signs of infection (redness, discharge) to your doctor.,Store CEQUA at room temperature (20-25°C); do not refrigerate or freeze.,It may take several weeks to notice improvement; continue use as prescribed even if you feel no effect initially.
Take exactly as prescribed; do not double dose if missed.,Avoid live vaccines during treatment and for 3 months after stopping.,Report any signs of infection, unexplained bruising/bleeding, or jaundice immediately.,Limit sun exposure and use sunscreen due to increased skin cancer risk.,Do not take allopurinol or other new medications without consulting doctor.,Maintain adequate hydration to reduce risk of hepatotoxicity.,Regular blood tests are required to monitor for side effects.
No interactions on record
"Azathioprine may reduce the therapeutic efficacy and cardiotoxic effects of digitoxin by accelerating its metabolism through induction of cytochrome P450 enzymes, particularly CYP3A4. This interaction can lead to decreased digitoxin serum concentrations, potentially resulting in loss of heart rate control in patients with atrial fibrillation or heart failure. Conversely, the cardiotoxic risk of digitoxin is diminished, but the therapeutic goal may be compromised."
"Azathioprine and fingolimod both suppress lymphocyte function, leading to additive or synergistic immunosuppression. This combination increases the risk of severe infections, including opportunistic infections, due to profound immune system suppression. Clinically, patients may present with prolonged lymphopenia, increased susceptibility to infections, and potential reactivation of latent viruses such as JC virus (causing progressive multifocal leukoencephalopathy) or cytomegalovirus."
"Azathioprine, an immunosuppressant that acts as a prodrug for 6-mercaptopurine, can increase the myelosuppressive effects of benazepril, an ACE inhibitor. This interaction is likely due to additive bone marrow suppression, leading to an elevated risk of leukopenia, anemia, and thrombocytopenia, especially in patients with renal impairment or concomitant use of other myelosuppressive agents."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about CEQUA vs AZATHIOPRINE, answered by our medical review team.
CEQUA is a Immunosuppressant that works by Immunosuppressant; binds to cyclophilin D in mitochondria, inhibiting opening of mitochondrial permeability transition pore (m PTP), which reduces T-lymphocyte activation and cytokine release. Also forms complex with cyclophilin A to inhibit calcineurin, suppressing IL-2 production and T-cell proliferation.. AZATHIOPRINE is a Immunosuppressant that works by Azathioprine is a purine analog that inhibits purine nucleotide synthesis, thereby suppressing DNA replication and cell proliferation. It is converted to 6-mercaptopurine, which acts as a purine antagonist, inhibiting de novo purine synthesis and interfering with RNA and DNA synthesis, particularly in rapidly dividing cells such as T-lymphocytes.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CEQUA and AZATHIOPRINE depend on the specific clinical indication. These are both Immunosuppressant agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of CEQUA is: Instill one drop of 0.09% ophthalmic solution in each eye twice daily, approximately 12 hours apart.. The standard adult dose of AZATHIOPRINE is: 1.5 to 2.5 mg/kg orally once daily; typical adult dose 50-150 mg/day orally. Intravenous dose is 3-5 mg/kg/day as a slow infusion over 30-60 minutes.. 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 CEQUA and AZATHIOPRINE 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. CEQUA is classified as Category C. CEQUA (cyclosporine ophthalmic solution) is classified as Pregnancy Category C. Animal studies have shown embryotoxic and fetotoxic effects at doses 0.2-0.8 times the human ocular . AZATHIOPRINE is classified as Category D/X. Azathioprine is pregnancy category D. First trimester: increased risk of congenital anomalies including ventricular septal defects, limb defects, and esophageal atresia. Second and. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.