NORMIFLO
Clinical safety rating: caution
Comprehensive clinical and safety monograph for NORMIFLO (NORMIFLO).
NORMIFLO is a selective alpha-1 adrenergic receptor antagonist that inhibits the binding of norepinephrine to alpha-1 receptors in the smooth muscle of the prostate and bladder neck, leading to relaxation of these muscles and improved urine flow.
| Metabolism | Primarily hepatic via CYP3A4 and CYP2D6 isoenzymes; undergoes extensive first-pass metabolism. |
| Excretion | Renal excretion of unchanged drug accounts for 65-75% of elimination; biliary/fecal excretion accounts for 20-30%, with the remainder as metabolites. |
| Half-life | Terminal elimination half-life is 8-12 hours in adults with normal renal function; prolonged to 20-30 hours in severe renal impairment (CrCl <30 mL/min). |
| Protein binding | Approximately 90-95% bound, primarily to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | Volume of distribution is 0.5-0.8 L/kg, indicating moderate tissue distribution. |
| Bioavailability | Oral bioavailability is 80-90% with moderate interindividual variability. |
| Onset of Action | Oral: 30-60 minutes; Intravenous: 2-5 minutes. |
| Duration of Action | Oral: 6-8 hours; Intravenous: 4-6 hours; duration is dose-dependent and may be extended in hepatic impairment. |
| Molecular Weight | 296.4 |
Adults: 75 mg orally once daily.
| Dosage form | INJECTABLE |
| Renal impairment | GFR ≥30 mL/min: No adjustment. GFR 15-29 mL/min: 50 mg once daily. GFR <15 mL/min: Not recommended. |
| Liver impairment | Child-Pugh A: No adjustment. Child-Pugh B: 50 mg once daily. Child-Pugh C: Not recommended. |
| Pediatric use | Children ≥6 years: 2 mg/kg orally once daily; maximum 75 mg. |
| Geriatric use | Adults ≥65 years: 50 mg once daily; monitor renal function. |
| 1st trimester | Avoid due to known teratogenic effects in animal studies; risk of congenital malformations. |
| 2nd trimester | Avoid; potential risk of fetal nephrotoxicity and oligohydramnios. |
| 3rd trimester | Avoid; risk of premature closure of ductus arteriosus and neonatal renal impairment. |
Clinical note
Comprehensive clinical and safety monograph for NORMIFLO (NORMIFLO).
| Placental transfer | Crosses placenta with measured cord blood levels approximately 10-20% of maternal serum levels. |
| Breastfeeding | Excreted in breast milk in low amounts; potential for adverse effects in infants such as renal impairment. Consider risk-benefit; avoid if possible. |
| Lactation Rating |
■ FDA Black Box Warning
None
| Serious Effects |
Hypersensitivity to any componentSevere renal impairment (eGFR <30 mL/min/1.73m²)Pregnancy
| Precautions | Orthostatic hypotension, especially at initiation of therapy or dose increase; advise patients to avoid sudden postural changes., Intraoperative floppy iris syndrome (IFIS) during cataract surgery., Caution in patients with severe hepatic impairment., Dizziness, syncope, and somnolence; avoid driving or hazardous activities until response is known. |
| Food/Dietary | Grapefruit/grapefruit juice may increase systemic exposure to fluticasone; avoid concurrent use. No other significant food interactions. |
Loading safety data…
| L4 - Possibly Hazardous |
| Teratogenic Risk | First trimester: Limited data, but based on animal studies and class effect (anti-androgen), risk of ambiguous genitalia in male fetuses (hypospadias) cannot be excluded. Second and third trimesters: Continued exposure may cause feminization of male fetuses due to androgen receptor blockade; also risk of preterm labor and fetal growth restriction. Avoid use in pregnancy unless no alternative. |
| Fetal Monitoring | Monitor maternal liver function tests, serum electrolytes, and blood pressure. In pregnant patients, perform fetal ultrasound for growth and anatomy, and assess amniotic fluid volume. Monitor for signs of preterm labor. |
| Fertility Effects | In males: may cause reversible oligospermia, decreased libido, and erectile dysfunction. In females: may disrupt menstrual cycle and inhibit ovulation. Fertility effects reverse after discontinuation. |
| Clinical Pearls |
| NORMIFLO (fluticasone propionate/salmeterol) is a combination ICS/LABA for maintenance treatment of asthma or COPD. Do not use for acute bronchospasm. Rinse mouth after each use to prevent oral candidiasis. Monitor for adrenal insufficiency during stress or dose reduction. In asthma, LABA use increases risk of asthma-related death; reserve for patients not controlled on low-medium dose ICS. |
| Patient Advice | Use regularly as prescribed, not for sudden breathing problems. · Rinse mouth with water after each use to prevent thrush. · Keep an emergency inhaler (e.g., albuterol) for acute symptoms. · Do not stop abruptly; taper under medical supervision. · Warn patients with COPD about increased pneumonia risk. |