Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
FASTIN vs ADVIL COLD AND SINUS
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Sympathomimetic amine that promotes release of norepinephrine and dopamine from presynaptic nerve terminals in the hypothalamus, suppressing appetite.
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2), reducing prostaglandin synthesis, leading to analgesic, anti-inflammatory, and antipyretic effects. Pseudoephedrine is a sympathomimetic amine that directly acts on alpha-adrenergic receptors in the nasal mucosa, causing vasoconstriction and reducing nasal congestion.
Short-term adjunct in exogenous obesity,Off-label: Attention deficit hyperactivity disorder (ADHD)
Temporary relief of sinus congestion and pressure,Temporary relief of nasal congestion,Temporary reduction of fever,Relief of minor aches and pains associated with the common cold or flu
30 mg orally once daily in the morning, administered as a single dose.
1-2 tablets (each containing ibuprofen 200 mg and pseudoephedrine 30 mg) orally every 4-6 hours as needed; maximum 6 tablets in 24 hours. Do not exceed 1200 mg ibuprofen and 180 mg pseudoephedrine per day.
Terminal elimination half-life is approximately 16-20 hours for the immediate-release formulation. With sustained-release forms, effective half-life may extend to 24-34 hours due to prolonged absorption. Clinical context: time to reach steady state is about 3-5 days.
Ibuprofen: 2-4 hours (terminal; rapid elimination, no accumulation with intermittent use). Pseudoephedrine: 4-8 hours (terminal; prolonged in alkaline urine, up to 16 hours at p H 8).
Hepatic metabolism via CYP3A4 and CYP2D6; active metabolite phendimetrazine (for some formulations).
Ibuprofen is primarily metabolized by CYP2C9 and CYP2C8. Pseudoephedrine is partially metabolized in the liver by N-demethylation.
Primarily renal (approximately 70-80% unchanged) and biliary/fecal (20-30% as metabolites). Urinary excretion is p H-dependent; acidic urine increases elimination.
Renal excretion of unchanged drug and metabolites: ibuprofen ~45-60% (primarily as conjugated metabolites, <10% unchanged), pseudoephedrine ~70-90% unchanged. Biliary/fecal elimination accounts for <10% for both components.
Approximately 40-50% bound to plasma proteins (albumin).
Ibuprofen: ~99% primarily to albumin. Pseudoephedrine: negligible (<10% bound to plasma proteins).
Approximately 3-5 L/kg. High Vd indicates extensive tissue distribution, including brain.
Ibuprofen: 0.1-0.2 L/kg (low Vd, indicating limited tissue distribution). Pseudoephedrine: 2.5-3.5 L/kg (high Vd, extensive tissue distribution including CNS).
Oral immediate-release: ~90% (high first-pass metabolism; absolute bioavailability is lower, but systemic exposure is adequate). Oral sustained-release: similar extent but with prolonged absorption.
Oral: ibuprofen ~80-100% (rapidly absorbed, no significant first-pass). Pseudoephedrine ~100% (well absorbed, minimal first-pass metabolism).
Contraindicated in severe renal impairment (e GFR <30 m L/min/1.73 m²). For moderate impairment (e GFR 30-59 m L/min/1.73 m²), reduce dose to 15 mg once daily.
GFR 30-89 m L/min: Use lowest effective dose for shortest duration; monitor renal function. GFR <30 m L/min or dialysis: Contraindicated.
Contraindicated in Child-Pugh class C cirrhosis. In Child-Pugh class A or B, initiate at 15 mg once daily and titrate cautiously to maximum 30 mg once daily.
Child-Pugh Class A: No adjustment; use with caution. Child-Pugh Class B or C: Avoid use.
Not recommended for pediatric patients under 16 years of age due to lack of safety and efficacy data.
Children <12 years: Do not use. Children ≥12 years: Same as adult dosing; 1-2 tablets every 4-6 hours as needed; maximum 6 tablets in 24 hours.
Initiating at 15 mg once daily is recommended due to increased sensitivity and potential for central nervous system adverse effects; maximum dose 30 mg once daily.
Use lowest effective dose for shortest duration; avoid chronic use. Reduce initial dose to 1 tablet every 6-8 hours due to increased risk of renal impairment, GI bleeding, and cardiovascular events.
None.
Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may increase with duration of use. Patients with cardiovascular disease or risk factors for cardiovascular disease may be at greater risk. NSAIDs are contraindicated for the treatment of perioperative pain in the setting of coronary artery bypass graft (CABG) surgery.
Cardiovascular events (hypertension, tachycardia, stroke), psychiatric adverse effects (psychosis, dependence), primary pulmonary hypertension, valvular heart disease, tolerance, withdrawal symptoms, glaucoma, hyperthyroidism, seizure disorder, diabetes (dose adjustment required), elderly patients (higher sensitivity).
Cardiovascular thrombotic events, gastrointestinal bleeding/ulceration/perforation, hypertension, renal toxicity, serious skin reactions, anaphylactoid reactions, exacerbation of asthma, and drug interactions including with ACE inhibitors, diuretics, and lithium.
Cardiovascular disease (e.g., coronary artery disease, arrhythmias, hypertension), hyperthyroidism, glaucoma, agitated states, history of drug abuse, MAOIs (concurrent or within 14 days), hypersensitivity to sympathomimetics.
Hypersensitivity to ibuprofen, aspirin, or other NSAIDs; history of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs; patients with severe hypertension or coronary artery disease; patients taking monoamine oxidase inhibitors (MAOIs) or within 14 days of stopping MAOIs; concurrent use of other sympathomimetics; in the setting of CABG surgery.
Avoid excessive caffeine intake (e.g., coffee, tea, cola, energy drinks) as it may potentiate CNS and cardiovascular effects. Grapefruit juice may alter drug metabolism; avoid concurrent consumption. Maintain a balanced, reduced-calorie diet as part of the weight loss plan. Alcohol should be avoided due to potential additive CNS effects.
Take with food or milk to reduce gastrointestinal irritation. Avoid alcohol consumption as it increases the risk of NSAID-related gastric ulcers and bleeding. High-sodium foods may exacerbate hypertension in patients sensitive to the pressor effects of pseudoephedrine.
FDA Pregnancy Category X. First trimester: Increased risk of oral clefts and cardiac malformations with amphetamine use. Second and third trimesters: Risk of premature delivery, low birth weight, and neonatal withdrawal syndrome. Avoid use in pregnancy.
First trimester: Ibuprofen (NSAID) is associated with increased risk of miscarriage and congenital malformations, particularly cardiac defects, with odds ratio 1.86 (95% CI 1.32-2.62) for any malformation and 1.86 (95% CI 1.32-2.62) for cardiac malformations. Second trimester: Risk of oligohydramnios and premature closure of ductus arteriosus after 20 weeks. Third trimester: Avoid after 30 weeks due to risk of premature ductus arteriosus closure and oligohydramnios; after 32 weeks, increased risk of necrotizing enterocolitis, intracranial hemorrhage, and renal impairment in neonate (renal agenesis/dysgenesis). Pseudoephedrine: First trimester – possible increased risk of gastroschisis (odds ratio 1.8, 95% CI 1.0-3.2) and small intestinal atresia. Second and third trimesters: potential uteroplacental vasoconstriction leading to fetal hypoxia; risk of prematurity and low birth weight.
Excreted in human milk; M/P ratio not established. Potential for adverse effects in nursing infants (irritability, poor feeding). Contraindicated during breastfeeding.
Ibuprofen: M/P ratio 0.005–0.006; low transfer into breast milk; AAP compatible; theoretical risk of platelet dysfunction in neonate. Pseudoephedrine: M/P ratio 2.6–3.5 (concentrated in milk); estimated infant dose 4.3% of maternal weight-adjusted dose; may cause irritability and sleep disturbances in infant; may reduce milk production by up to 24%. Caution advised; avoid in lactation if possible.
Contraindicated in pregnancy; no dose adjustments recommended.
Ibuprofen: No dose adjustment required; however, use lowest effective dose and shortest duration; avoid after 30 weeks gestation. Pseudoephedrine: No specific dose adjustment recommended based on pharmacokinetic changes, but use with caution due to vasoconstrictive effects; reduced efficacy may be observed due to increased plasma volume and renal clearance.
Fastin (phentermine) is a sympathomimetic amine indicated for short-term (up to 12 weeks) monotherapy for obesity. It should be used in conjunction with a reduced-calorie diet and exercise. Avoid co-administration with MAOIs or within 14 days of MAOI use due to hypertensive crisis risk. Use with caution in patients with hypertension, diabetes, or history of drug abuse. Monitor blood pressure and heart rate regularly. Tachyphylaxis may develop; discontinue if tolerance occurs. Do not use in patients with advanced arteriosclerosis, hyperthyroidism, glaucoma, or agitated states.
Advil Cold and Sinus is a fixed-dose combination of ibuprofen (NSAID) and pseudoephedrine (decongestant). Ibuprofen inhibits COX-1/2, reducing prostaglandin synthesis, while pseudoephedrine is an α-adrenergic agonist causing vasoconstriction in nasal mucosa. Use cautiously in patients with hypertension, cardiovascular disease, or renal impairment due to pseudoephedrine's pressor effects and ibuprofen's potential to reduce renal blood flow and antagonize antihypertensives. Avoid in patients with severe coronary artery disease, uncontrolled hypertension, or concurrent MAOI use. Max duration: 3 days for sinus symptoms, 5 days for pain. Monitor for NSAID-induced GI bleeding, especially in elderly or those on anticoagulants/aspirin.
Take Fastin exactly as prescribed, usually once daily in the morning to avoid insomnia.,Do not crush or chew the extended-release capsule; swallow whole.,Avoid taking late in the day to prevent difficulty sleeping.,Report any chest pain, palpitations, shortness of breath, or dizziness immediately.,Do not increase dose or take more frequently than prescribed; risk of dependence and side effects.,Fastin is for short-term use only (up to 12 weeks) and should be combined with a reduced-calorie diet and exercise.,Do not use if you have taken an MAO inhibitor in the last 14 days.,Avoid alcohol and other CNS stimulants (e.g., caffeine in large amounts) as they may increase side effects.,Do not stop abruptly; follow your doctor's instructions for tapering off.,Keep out of reach of children; misuse can cause severe cardiac toxicity.
Do not take more than directed; do not exceed 6 caplets in 24 hours.,Avoid use with other products containing ibuprofen or other NSAIDs, including aspirin, to prevent overdose and serious side effects.,Discontinue use and seek medical attention if symptoms worsen, persist >3 days for sinus or >5 days for pain, or if new symptoms occur.,Take with food or milk to reduce stomach upset; avoid alcohol to lower risk of GI bleeding.,If you have high blood pressure, heart disease, thyroid disease, diabetes, or difficulty urinating due to prostate enlargement, consult a doctor before use.,Do not use if you are taking a prescription monoamine oxidase inhibitor (MAOI) or for 2 weeks after stopping an MAOI drug.,Pregnant or breastfeeding women should not use this product; ibuprofen is contraindicated in third trimester due to risk of premature closure of ductus arteriosus.,Store at room temperature away from moisture and heat.
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 FASTIN vs ADVIL COLD AND SINUS, answered by our medical review team.
FASTIN is a Sympathomimetic Anorectic that works by Sympathomimetic amine that promotes release of norepinephrine and dopamine from presynaptic nerve terminals in the hypothalamus, suppressing appetite.. ADVIL COLD AND SINUS is a NSAID/Decongestant Combination that works by Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2), reducing prostaglandin synthesis, leading to analgesic, anti-inflammatory, and antipyretic effects. Pseudoephedrine is a sympathomimetic amine that directly acts on alpha-adrenergic receptors in the nasal mucosa, causing vasoconstriction and reducing nasal congestion.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between FASTIN and ADVIL COLD AND SINUS 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 FASTIN is: 30 mg orally once daily in the morning, administered as a single dose.. The standard adult dose of ADVIL COLD AND SINUS is: 1-2 tablets (each containing ibuprofen 200 mg and pseudoephedrine 30 mg) orally every 4-6 hours as needed; maximum 6 tablets in 24 hours. Do not exceed 1200 mg ibuprofen and 180 mg pseudoephedrine per day.. 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 FASTIN and ADVIL COLD AND SINUS 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. FASTIN is classified as Category C. FDA Pregnancy Category X. First trimester: Increased risk of oral clefts and cardiac malformations with amphetamine use. Second and third trimesters: Risk of premature delivery, lo. ADVIL COLD AND SINUS is classified as Category C. First trimester: Ibuprofen (NSAID) is associated with increased risk of miscarriage and congenital malformations, particularly cardiac defects, with odds ratio 1.86 (95% CI 1.32-2.. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.