Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ADVIL PM vs ACULAR
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis. Diphenhydramine is a first-generation antihistamine that antagonizes histamine H1 receptors, causing sedation.
Nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis, which decreases inflammation, pain, and fever.
Temporary relief of occasional sleeplessness associated with minor aches and pains
Treatment of postoperative inflammation in patients who have undergone cataract extraction,Relief of ocular itching due to seasonal allergic conjunctivitis
Two caplets (ibuprofen 200 mg, diphenhydramine citrate 38 mg) orally at bedtime as needed for insomnia. Maximum: 2 caplets in 24 hours.
One drop of 0.5% ophthalmic solution into the affected eye(s) four times daily.
Ibuprofen: 2-4 hours (terminal); clinical context: steady state achieved in 1 day, not affected by renal impairment. Diphenhydramine: 4-8 hours (terminal); clinical context: prolonged in hepatic impairment.
Terminal half-life: 1.8 hours (ketorolac tromethamine); clinical context: short half-life supports dosing every 6 hours for acute pain, but prolonged in elderly or renal impairment (↑ to 5-6 hours, thus dose reduction required).
Ibuprofen is primarily metabolized via hepatic oxidation by CYP2C9. Diphenhydramine is metabolized via hepatic N-demethylation and oxidation, primarily by CYP2D6.
Hepatic metabolism primarily via cytochrome P450 2C9 (CYP2C9).
Ibuprofen: Renal (90% as metabolites and conjugates, <10% unchanged); Diphenhydramine: Renal (primarily as metabolites, ~1% unchanged). Fecal excretion is negligible for both.
Renal: ~80% as unchanged drug and glucuronide conjugates; biliary/fecal: ~20%
Ibuprofen: >99% bound to albumin; Diphenhydramine: 78-85% bound to albumin.
99% bound; primary binding protein: albumin.
Ibuprofen: 0.1-0.2 L/kg; small Vd consistent with high protein binding. Diphenhydramine: 4.5-8.5 L/kg; large Vd indicating extensive tissue distribution.
0.11-0.25 L/kg; clinical meaning: low Vd indicates primarily confined to extracellular compartment (plasma and interstitial fluid), minimal tissue penetration.
Ibuprofen: 80-100% (oral); Diphenhydramine: 50-70% (oral) due to first-pass metabolism.
Ophthalmic: ~2% systemic absorption after topical instillation (due to corneal permeability and nasolacrimal drainage); oral formulation not used for Acular (ophthalmic only).
Avoid use in GFR <30 m L/min. For GFR 30-59 m L/min, limit to single dose and avoid chronic use. No adjustment needed for GFR ≥60 m L/min.
No dosage adjustment required for renal impairment.
Contraindicated in Child-Pugh Class C. In Child-Pugh Class B, reduce dose by 50% (max 1 caplet) and monitor for toxicity. No adjustment for Child-Pugh Class A.
No dosage adjustment required for hepatic impairment.
Not recommended for children under 12 years. For age ≥12 years, same adult dose: 2 caplets at bedtime.
Safety and efficacy in pediatric patients have not been established; use not recommended.
Start with lowest effective dose (1 caplet) at bedtime to minimize anticholinergic and GI adverse effects. Avoid in elderly with cognitive impairment or high fall risk.
No specific dosage adjustment required; use same dosing as for younger adults.
NSAIDs cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use. NSAIDs are contraindicated in the setting of coronary artery bypass graft (CABG) surgery.
No FDA boxed warning.
Cardiovascular thrombotic events,Gastrointestinal bleeding, ulceration, and perforation,Renal toxicity,Sedation and impaired cognitive function,Anticholinergic effects,Avoid use with other NSAIDs or antihistamines,Use caution in elderly, renal impairment, hepatic impairment, and pregnancy
May increase bleeding time due to inhibition of platelet aggregation; use with caution in patients with known bleeding tendencies or those receiving other medications that may prolong bleeding time.,May cause corneal effects including keratitis and corneal thinning; discontinue if corneal epithelial breakdown occurs.,Use with caution in patients with prior sensitivity to aspirin, phenylacetic acid derivatives, or other NSAIDs.,May delay wound healing or exacerbate infections; avoid use in patients with active epithelial herpes simplex keratitis.
Hypersensitivity to ibuprofen, diphenhydramine, or any component of the formulation,History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs,Perioperative pain in the setting of coronary artery bypass graft (CABG) surgery,Neonates and premature infants (due to diphenhydramine),Concurrent use with other diphenhydramine products or sedatives
Hypersensitivity to ketorolac tromethamine or any component of the formulation,History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs,Active epithelial herpes simplex keratitis,Late pregnancy (third trimester) due to risk of premature closure of ductus arteriosus
Take with food or milk to reduce GI upset. Avoid alcohol and grapefruit juice. Caffeine may enhance CNS stimulation and should be limited.
No known food interactions. Avoid alcohol if concomitant oral NSAIDs are used due to increased risk of gastrointestinal bleeding, but this is not specific to ophthalmic use.
Pregnancy Category C/D (after 30 weeks). First trimester: Potential risk of miscarriage and cardiac defects (limited data with NSAIDs). Second trimester: Avoid unless clearly needed; possible oligohydramnios, premature closure of ductus arteriosus, and fetal renal impairment. Third trimester: Contraindicated after 30 weeks due to risk of premature ductus arteriosus closure and persistent pulmonary hypertension.
Pregnancy Category C. No adequate studies in pregnant women. Ketorolac tromethamine, like other NSAIDs, may cause premature closure of the ductus arteriosus and fetal renal impairment in the third trimester. First and second trimester use should be avoided unless clearly needed. The potential benefits should be weighed against the risks.
Diphenhydramine and ibuprofen are excreted into breast milk. M/P ratio not established. Both drugs are considered compatible with breastfeeding in low doses, but theoretical risk of infant sedation (diphenhydramine) and gastrointestinal effects (ibuprofen). Max daily dose for mother should not exceed recommended limits. Monitor infant for drowsiness and poor feeding.
Ketorolac is excreted in human milk at low levels. The M/P ratio is not well defined. Due to potential adverse effects in nursing infants, caution is advised. Use only if clearly indicated and consider alternative agents.
No specific dose adjustment recommended for ibuprofen or diphenhydramine in pregnancy. However, due to altered pharmacokinetics (increased volume of distribution, renal clearance), standard doses may be less effective. Avoid use if possible, especially after 30 weeks. Use lowest effective dose for shortest duration.
No specific dose adjustments are recommended for pregnancy; however, use the lowest effective dose for the shortest duration due to potential fetal risks. Physiological changes in pregnancy (increased volume of distribution, renal clearance) may alter pharmacokinetics, but no formal studies justify dose modification.
Advil PM combines ibuprofen (NSAID) and diphenhydramine (antihistamine). Avoid concomitant use with other NSAIDs or CNS depressants (including alcohol). Use lowest effective dose for shortest duration. Contraindicated in severe hepatic/renal impairment, active GI bleeding, or during third trimester of pregnancy. May cause morning drowsiness due to antihistamine.
ACULAR (ketorolac tromethamine ophthalmic solution) is a nonsteroidal anti-inflammatory drug (NSAID) used for ocular inflammation. Avoid concomitant use with other NSAIDs or corticosteroids due to increased risk of corneal adverse events. Use with caution in patients with bleeding disorders or those on anticoagulants, as it may increase bleeding tendency. Monitor for corneal toxicity, especially in patients with compromised corneal integrity. Ensure proper storage at room temperature and discard if solution changes color or becomes cloudy.
Take only one tablet before bedtime; do not exceed recommended dose.,Avoid alcohol and other sedatives while using this medication.,Do not use for more than 10 days for pain or 3 days for fever unless directed by a doctor.,May cause drowsiness; avoid driving or operating machinery until you know how the drug affects you.,Not for use in children under 12 years of age or during pregnancy/breastfeeding without consulting a healthcare provider.,Report signs of stomach bleeding (e.g., black/tarry stools, vomiting blood) or allergic reactions (e.g., facial swelling, difficulty breathing).
Do not touch the dropper tip to any surface to avoid contamination.,Remove contact lenses before instillation and wait at least 15 minutes before reinserting.,Apply pressure to the inner corner of the eye (nasolacrimal occlusion) for 1 minute after instillation to reduce systemic absorption.,Do not use while wearing soft contact lenses, as the preservative may be absorbed.,Report any signs of corneal problems such as pain, redness, or vision changes immediately.,Use exactly as prescribed and do not share the medication with others.
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 ADVIL PM vs ACULAR, answered by our medical review team.
ADVIL PM is a NSAID/Sedative Combination that works by Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis. Diphenhydramine is a first-generation antihistamine that antagonizes histamine H1 receptors, causing sedation.. ACULAR is a NSAID Ophthalmic that works by Nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis, which decreases inflammation, pain, and fever.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ADVIL PM and ACULAR 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 ADVIL PM is: Two caplets (ibuprofen 200 mg, diphenhydramine citrate 38 mg) orally at bedtime as needed for insomnia. Maximum: 2 caplets in 24 hours.. The standard adult dose of ACULAR is: One drop of 0.5% ophthalmic solution into the affected eye(s) four times daily.. 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 ADVIL PM and ACULAR 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. ADVIL PM is classified as Category C. Pregnancy Category C/D (after 30 weeks). First trimester: Potential risk of miscarriage and cardiac defects (limited data with NSAIDs). Second trimester: Avoid unless clearly neede. ACULAR is classified as Category C. Pregnancy Category C. No adequate studies in pregnant women. Ketorolac tromethamine, like other NSAIDs, may cause premature closure of the ductus arteriosus and fetal renal impairm. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.