VOLMAX
Clinical safety rating: caution
Comprehensive clinical and safety monograph for VOLMAX (VOLMAX).
Beta-2 adrenergic receptor agonist; stimulates adenylate cyclase, increasing cyclic AMP, leading to bronchodilation.
| Metabolism | Hepatic, via CYP3A4 and conjugation; extensive first-pass metabolism. |
| Excretion | Renal: 60-70% (unchanged and metabolites); fecal: 15-25%; biliary: <5%. |
| Half-life | Terminal elimination half-life: 4-6 hours. Clinical context: requires twice-daily dosing in asthma. |
| Protein binding | 40-50% bound to albumin. |
| Volume of Distribution | 1.5-2.0 L/kg, indicating extensive tissue distribution. |
| Bioavailability | Oral: 40-60% (first-pass metabolism). |
| Onset of Action | Oral: 30-60 minutes (bronchodilation). |
| Duration of Action | 12 hours (sustained bronchodilation from extended-release formulation). |
| Molecular Weight | 516.6 |
Adults: 4-8 mg orally every 12 hours (sustained-release); maximum 16 mg every 12 hours.
| Dosage form | TABLET, EXTENDED RELEASE |
| Renal impairment | No specific guidelines; use with caution in severe renal impairment (CrCl <30 mL/min) due to potential for increased systemic exposure. |
| Liver impairment | Child-Pugh Class A: no adjustment; Class B: reduce dose by 50%; Class C: avoid use. |
| Pediatric use | Children 2-5 years: 0.1 mg/kg/dose every 12 hours (max 4 mg/dose); 6-12 years: 2-4 mg every 12 hours; >12 years: same as adult. |
| Geriatric use | Start at lower end of dosing range (2-4 mg every 12 hours) due to decreased renal function and increased sensitivity. |
| 1st trimester | Category C: No adequate studies in pregnant women; use only if potential benefit justifies potential risk to fetus. |
| 2nd trimester | Category C: Same as first trimester; may cause premature labor due to tocolytic effects. |
| 3rd trimester | Category C: Risk of maternal cardiac effects and fetal hypoglycemia. |
Clinical note
Comprehensive clinical and safety monograph for VOLMAX (VOLMAX).
| Placental transfer | Crosses placenta in animal studies; human data limited. |
| Breastfeeding | Excreted in breast milk in small amounts; potential for infant tachycardia. Use with caution, monitor infant for adverse effects. |
| Lactation Rating |
■ FDA Black Box Warning
None.
| Serious Effects |
Hypersensitivity to albuterol or any componentCardiac arrhythmias associated with tachycardiaTocolytic use in pregnant women at risk of premature labor (should be avoided in certain conditions)
| Precautions | Paradoxical bronchospasm, Cardiovascular effects (tachycardia, arrhythmia, hypertension), Hypokalemia, Hyperglycemia, Immediate hypersensitivity reactions |
| Food/Dietary | Avoid excessive caffeine intake (coffee, tea, cola, chocolate) as it may increase the risk of nervousness, tremor, and palpitations. No specific food restrictions; take with or without food. Grapefruit juice is not known to interact, but consult your doctor. |
Loading safety data…
| L3: Limited Data |
| Teratogenic Risk | FDA Pregnancy Category C. First trimester: No well-controlled studies; potential for fetal tachycardia and hypoglycemia based on beta-2 agonist class effects. Second and third trimesters: May cause fetal tachycardia, hypoglycemia, and maternal hyperglycemia; risk of premature labor inhibition. Use only if benefit outweighs risk. |
| Fetal Monitoring | Monitor maternal blood pressure, heart rate, serum glucose, and electrolytes. Fetal heart rate monitoring during labor if used for tocolysis; assess for signs of pulmonary edema in prolonged use. |
| Fertility Effects | No known adverse effects on fertility in animal studies; no human data available. Beta-2 agonists may theoretically inhibit uterine contractions but no direct impact on conception. |
| Clinical Pearls |
| Volmax (albuterol extended-release) provides bronchodilation for 12 hours; avoid use with non-selective beta-blockers due to risk of bronchospasm. Monitor serum potassium levels as beta-2 agonists can cause hypokalemia, especially at high doses. Tachyphylaxis may occur with prolonged use; consider rescue inhaler for acute symptoms. |
| Patient Advice | Take this medication exactly as prescribed, usually every 12 hours. Swallow the tablet whole; do not crush, chew, or break it. · If you miss a dose, take it as soon as you remember unless it is almost time for your next dose. Do not double the dose to catch up. · Common side effects include trembling, nervousness, headache, increased heart rate, and palpitations. Contact your doctor if these persist or worsen. · This medication can cause dizziness or blurred vision; avoid driving or operating machinery until you know how it affects you. · Inform your healthcare provider about all other medications you are taking, especially beta-blockers, diuretics, and MAO inhibitors. · Seek emergency medical attention if you experience chest pain, irregular heartbeat, or signs of allergic reaction (rash, hives, swelling, severe dizziness, trouble breathing). |