JUNIOR STRENGTH MOTRIN
Clinical safety rating: caution
Comprehensive clinical and safety monograph for JUNIOR STRENGTH MOTRIN (JUNIOR STRENGTH MOTRIN).
Cyclooxygenase (COX-1 and COX-2) inhibitor, reducing prostaglandin synthesis, thereby decreasing inflammation, pain, and fever.
| Metabolism | Primarily hepatic via CYP2C9, with minor contributions from CYP2C8 and glucuronidation. |
| Excretion | Renal excretion of inactive metabolites and conjugates (>90%); less than 10% excreted unchanged. Fecal elimination minor (<5%). |
| Half-life | 1.5-2 hours in children; prolonged in neonates (up to 30 hours) and renal impairment. Clinical: short half-life requires frequent dosing for sustained antipyresis/analgesia. |
| Protein binding | 99% bound to albumin. |
| Volume of Distribution | 0.2 L/kg in children; low Vd indicates limited tissue distribution and high plasma protein binding. Clinical: mainly confined to vascular compartment. |
| Bioavailability | Oral: 80-100% (rapid absorption); rectal: approximately 70-80%. |
| Onset of Action | Oral: 30-60 minutes for antipyresis; 1-2 hours for analgesia. |
| Duration of Action | 4-6 hours for fever reduction; 6-8 hours for pain relief. Duration shorter than adults due to faster clearance. |
| Molecular Weight | 206.28 |
200-400 mg orally every 4-6 hours as needed; maximum 1200 mg/day without prescription.
| Dosage form | TABLET, CHEWABLE |
| Renal impairment | GFR 30-59 mL/min: reduce dose by 50% or avoid; GFR <30 mL/min: contraindicated. |
| Liver impairment | Child-Pugh class A: no adjustment; Child-Pugh class B: reduce dose by 50%; Child-Pugh class C: avoid use. |
| Pediatric use | 6 months to 12 years: 5-10 mg/kg per dose orally every 6-8 hours; maximum 40 mg/kg/day. |
| Geriatric use | Initiate at lowest effective dose; consider renal function; increase dosing interval to every 6-8 hours. |
| 1st trimester | Avoid use, especially during first trimester, due to risk of miscarriage and congenital malformations (e.g., cardiac defects, gastroschisis). NSAIDs should be avoided if possible. |
| 2nd trimester | Use with caution; may be used if clearly needed, but avoid during 20 weeks and later due to risk of oligohydramnios from fetal renal effects. |
| 3rd trimester | Avoid use; may cause premature closure of ductus arteriosus, oligohydramnios, and fetal renal impairment. Avoid after 30 weeks gestation. |
Clinical note
Comprehensive clinical and safety monograph for JUNIOR STRENGTH MOTRIN (JUNIOR STRENGTH MOTRIN).
| Placental transfer | Ibuprofen crosses the placenta. Fetal-to-maternal ratio ~0.001-0.003 in humans; limited but measurable transfer. |
| Breastfeeding | Ibuprofen is excreted into breast milk in low amounts (estimated infant dose ~0.0008% of maternal weight-adjusted dose). Considered compatible with breastfeeding; use lowest effective dose for shortest duration. |
■ FDA Black Box Warning
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.
| Common Effects | Stomach pain Nausea Diarrhea |
| Serious Effects |
Hypersensitivity to ibuprofen or any NSAIDHistory of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDsActive peptic ulcer disease or GI bleedingSevere renal impairment (eGFR <30 mL/min/1.73 m²)Severe hepatic impairmentThird trimester of pregnancyPerioperative pain in setting of coronary artery bypass graft (CABG) surgery
| Precautions | Risk of GI ulceration, bleeding, and perforation; increased cardiovascular thrombotic events; hypertension; fluid retention and edema; severe skin reactions (e.g., Stevens-Johnson syndrome); renal toxicity, especially in patients with impaired renal function; anaphylactoid reactions. |
Loading safety data…
| Lactation Rating | L1 (Compatible) |
| Teratogenic Risk | First trimester: Increased risk of miscarriage and congenital malformations (cardiac, gastroschisis) with NSAID use; a causal relationship has not been firmly established. Second trimester: Generally considered lower risk, but avoid prolonged use. Third trimester: Known association with premature closure of the ductus arteriosus, oligohydramnios, and fetal renal dysfunction; contraindicated after 30 weeks gestation. |
| Fetal Monitoring | Monitor maternal renal function, blood pressure, and signs of gastrointestinal bleeding. For prolonged use or use after 20 weeks gestation, fetal ultrasound to assess amniotic fluid volume and ductus arteriosus patency. Consider fetal echocardiography if used near term. |
| Fertility Effects | Ibuprofen may impair female fertility by interfering with ovulation through inhibition of prostaglandin synthesis. Effects are reversible upon discontinuation. No known adverse effects on male fertility. |
| Food/Dietary | Take with food or milk to minimize gastrointestinal irritation. Avoid alcohol while taking this medication as it increases risk of stomach bleeding. |
| Clinical Pearls | For pediatric patients, use weight-based dosing (5-10 mg/kg/dose) rather than age-based to ensure efficacy and safety. Limit to 4 doses per day; maximum 40 mg/kg/day or 1.2 g/day, whichever is less. Do not combine with other NSAIDs. Use lowest effective dose for shortest duration. Contraindicated in children with active peptic ulcer disease, severe renal impairment, or known hypersensitivity to ibuprofen or aspirin. |
| Patient Advice | Give with food or milk to reduce stomach upset. · Use weight-based dosing: shake suspension well before use; use dosing syringe or cup provided. · Do not exceed 4 doses in 24 hours; wait at least 4 hours between doses. · Do not give with other pain relievers containing ibuprofen, naproxen, or aspirin. · Stop use and consult doctor if pain worsens or lasts more than 10 days, or if fever lasts more than 3 days. · Seek medical help immediately if signs of allergic reaction (rash, hives, swelling, trouble breathing) or stomach bleeding (bloody or black stools, vomit that looks like coffee grounds) occur. |