Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ZYDELIG vs TENUATE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Idelalisib is a selective inhibitor of phosphatidylinositol 3-kinase delta (PI3Kδ), blocking the PI3K/AKT signaling pathway, leading to reduced proliferation, survival, and migration of malignant B cells.
Tenuate (diethylpropion) is a sympathomimetic amine that acts as an appetite suppressant. It stimulates the release of norepinephrine and to a lesser extent dopamine from presynaptic nerve terminals in the hypothalamus, increasing satiety.
Relapsed chronic lymphocytic leukemia (CLL) in combination with rituximab,Relapsed follicular B-cell non-Hodgkin lymphoma (FL) in patients who have received at least two prior systemic therapies,Relapsed small lymphocytic lymphoma (SLL) in patients who have received at least two prior systemic therapies
FDA-approved: short-term (up to 12 weeks) adjunct in a regimen of weight reduction based on caloric restriction in patients with exogenous obesity.,Off-label: long-term management of obesity (not FDA-approved for extended use).
150 mg orally twice daily, taken with food.
25 mg orally three times daily before meals, or 75 mg extended-release orally once daily in the morning.
Terminal elimination half-life is 6.5 hours (range 4-10 hours) after oral administration, supporting twice-daily dosing.
4-6 hours (terminal); clinical context: short half-life supports multiple daily dosing
Primarily metabolized by aldehyde oxidase (AO) and CYP3A4, with minor contributions from UGT1A4.
Extensively metabolized in the liver via N-dealkylation to active metabolites (ethylaminopropiophenone and diethylaminopropiophenone). Enzymes involved include CYP3A4 and CYP2D6.
Primarily hepatic metabolism, with 44% of dose excreted in feces (as metabolites) and 22% in urine (unchanged drug and metabolites).
Renal (90% as metabolites, ~10% unchanged); minor biliary/fecal (<10%)
84% bound to plasma proteins, primarily to albumin and alpha-1-acid glycoprotein.
~92% (primarily albumin)
Mean volume of distribution is 113 L (approximately 1.4 L/kg), indicating extensive tissue distribution.
~4 L/kg (extensive tissue distribution, including CNS)
Absolute oral bioavailability is 40% (range 30-50%) due to first-pass metabolism.
Oral: ~60-70% (first-pass metabolism)
No dose adjustment required for mild to moderate renal impairment (Cr Cl ≥30 m L/min). For severe renal impairment (Cr Cl <30 m L/min), not recommended due to lack of data.
No specific guidelines; use with caution in severe renal impairment (GFR <30 m L/min) due to potential accumulation.
Child-Pugh Class A: No dose adjustment. Child-Pugh Class B: Reduce dose to 100 mg twice daily. Child-Pugh Class C: Not recommended.
Contraindicated in Child-Pugh Class C; use with caution in Class A and B, consider dose reduction.
Safety and efficacy not established for patients <18 years.
Not recommended for children under 16 years of age.
No specific dose adjustment recommended, but monitor for age-related renal and hepatic function changes.
Initial dose at 12.5 mg twice daily; titrate slowly due to increased sensitivity and risk of adverse effects.
WARNING: FATAL AND SERIOUS TOXICITIES: Hepatic, severe diarrhea/colitis, pneumonitis, and intestinal perforation. Fatal and/or serious hepatotoxicity occurred in 18% of patients. Fatal and/or serious diarrhea or colitis occurred in 14%. Fatal and/or serious pneumonitis occurred in 4%. Fatal and/or serious intestinal perforation occurred in <1%.
There is no FDA boxed warning for Tenuate.
Hepatotoxicity: Monitor liver function tests,Severe diarrhea/colitis: Manage with supportive care and corticosteroids,Pneumonitis: Interrupt therapy and evaluate,Intestinal perforation: Discontinue if suspected,Infections: Monitor for opportunistic infections, including CMV,Neutropenia: Monitor blood counts,Embryofetal toxicity: Can cause fetal harm,Vaccinations: Avoid live vaccines during treatment
Primary pulmonary hypertension: rare but serious condition associated with use.,Cardiac valvulopathy: risk increases with prolonged use or combination with other serotonergic drugs.,Tachyphylaxis: tolerance to anorectic effects may develop within a few weeks.,Psychiatric effects: may exacerbate psychiatric disorders, particularly in patients with history of substance abuse.,Seizures: risk increased in patients with epilepsy or history of seizures.
History of severe hypersensitivity (e.g., anaphylaxis, Stevens-Johnson syndrome) to idelalisib or any excipient
Hypersensitivity to diethylpropion or other sympathomimetic amines.,Advanced arteriosclerosis, cardiovascular disease, moderate to severe hypertension, hyperthyroidism, glaucoma.,History of drug abuse, agitated states.,Concurrent use (or within 14 days of discontinuing) MAO inhibitors (hypertensive crisis risk).
Avoid grapefruit and grapefruit juice (CYP3A4 inhibition increases idelalisib exposure). Take with food to reduce nausea and diarrhea.
Avoid caffeine and other stimulants (e.g., in coffee, tea, cola, energy drinks) as they may increase cardiovascular side effects. Avoid high-tyramine foods (e.g., aged cheeses, cured meats, fermented products) if also taking MAOIs, but this is relevant only if transitioning therapy. No specific food restrictions otherwise, but a reduced-calorie diet is essential for efficacy.
Pregnancy Category D. First trimester: Risk of fetal malformations including neural tube defects and craniofacial anomalies based on animal studies showing embryo-fetal toxicity and teratogenicity. Second and third trimesters: Risk of fetal hematologic toxicity (leukopenia, neutropenia) and potential growth restriction. Counsel women of childbearing age to use effective contraception during treatment and for 1 month after last dose.
First trimester: Limited human data, but animal studies suggest increased risk of cardiovascular and neural tube defects. Second and third trimesters: Associated with reduced fetal growth and neonatal withdrawal symptoms (tremors, hypertonia, feeding difficulties). Avoid use unless clearly needed.
No human data on presence in breast milk; risk of serious adverse reactions in breastfed infants (immunosuppression, neutropenia). M/P ratio not determined. Advise not to breastfeed during treatment and for 1 week after last dose.
Excreted in human milk; M/P ratio not determined. Potential for adverse effects in nursing infants (e.g., irritability, poor weight gain). Use caution; decision to discontinue nursing or drug based on importance to mother.
No dose adjustment studies in pregnant women. Due to increased volume of distribution and altered clearance in pregnancy, therapeutic drug monitoring is not established. Use minimum effective dose. If used during pregnancy, monitor for maternal neutropenia, infections, and adjust dose per standard ANC thresholds (hold if ANC < 500/mm³; resume at reduced dose when ANC > 1000/mm³).
No specific pharmacokinetic data; however, pregnancy may alter metabolism. Start with lowest effective dose (25 mg BID) and monitor clinical response. Avoid sustained-release formulations due to altered GI transit.
Monitor for hepatotoxicity (ALT/AST elevations), severe cutaneous reactions (Stevens-Johnson syndrome), and pneumonitis. Requires hepatic function monitoring every 2 weeks for first 2 months, then monthly. Contraindicated with CYP3A4 inducers or strong inhibitors due to metabolism via CYP3A4. Dose reduction needed for moderate hepatic impairment (Child-Pugh B).
Tenuate (diethylpropion) is a sympathomimetic amine anorectic indicated for short-term (8-12 weeks) adjunct in obesity management. Avoid in patients with history of drug abuse, cardiovascular disease, hyperthyroidism, or glaucoma. Monitor blood pressure and heart rate regularly. Tolerance may develop; discontinue if tolerance occurs. Contraindicated with MAOIs or within 14 days of their use. May impair ability to drive or operate machinery.
Take with food to reduce gastrointestinal side effects.,Avoid grapefruit and grapefruit juice during treatment.,Report any signs of liver problems (jaundice, dark urine, abdominal pain) or skin reactions (rash, blisters) immediately.,Use effective contraception during and for at least 1 month after treatment.,Do not stop or change dose without consulting your healthcare provider.
Take exactly as prescribed; do not increase dose or duration.,May cause dizziness or blurred vision; avoid driving if affected.,Inform your doctor if you have heart disease, high blood pressure, or thyroid problems.,Avoid alcohol and other CNS stimulants while taking this medication.,Report any chest pain, palpitations, or severe headache immediately.,Do not take with other appetite suppressants without consulting your doctor.,This medication is only for short-term use; combine with diet and exercise.
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 ZYDELIG vs TENUATE, answered by our medical review team.
ZYDELIG is a PI3K Inhibitor Antineoplastic that works by Idelalisib is a selective inhibitor of phosphatidylinositol 3-kinase delta (PI3Kδ), blocking the PI3K/AKT signaling pathway, leading to reduced proliferation, survival, and migration of malignant B cells.. TENUATE is a Sympathomimetic anorectic that works by Tenuate (diethylpropion) is a sympathomimetic amine that acts as an appetite suppressant. It stimulates the release of norepinephrine and to a lesser extent dopamine from presynaptic nerve terminals in the hypothalamus, increasing satiety.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ZYDELIG and TENUATE 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 ZYDELIG is: 150 mg orally twice daily, taken with food.. The standard adult dose of TENUATE is: 25 mg orally three times daily before meals, or 75 mg extended-release orally once daily in the morning.. 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 ZYDELIG and TENUATE 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. ZYDELIG is classified as Category C. Pregnancy Category D. First trimester: Risk of fetal malformations including neural tube defects and craniofacial anomalies based on animal studies showing embryo-fetal toxicity an. TENUATE is classified as Category C. First trimester: Limited human data, but animal studies suggest increased risk of cardiovascular and neural tube defects. Second and third trimesters: Associated with reduced fetal. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.