Ibuprofen

Ibuprofen is an NSAID approved across multiple products and formulations for pain relief, fever reduction, and inflammation — with specific indications varying by product and route.

• Oral OTC tablets and capsules (including Advil, Care One, Equate, and many store brands): temporarily relieve minor aches and pains from headache, backache, toothache, muscular aches, menstrual cramps, minor arthritis pain, and the common cold; temporarily reduce fever
• Ibu oral prescription tablets: relief of signs and symptoms of rheumatoid arthritis and osteoarthritis; relief of mild to moderate pain; treatment of primary dysmenorrhea (painful periods)
• Caldolor (intravenous injection) for adults and pediatric patients aged 3 months and older: management of mild to moderate pain; management of moderate to severe pain as an adjunct (add-on) to opioid pain medicines; reduction of fever
• Ibuprofen Lysine (intravenous solution) for premature infants: closure of a clinically significant patent ductus arteriosus (PDA — an abnormal blood vessel connection near the heart) in premature infants weighing 500–1500 g at no more than 32 weeks gestational age, when standard medical management has not worked

Ibuprofen blocks two enzymes — COX-1 and COX-2 — that the body uses to produce prostaglandins. Prostaglandins are signaling molecules that sensitize pain receptors, drive inflammation, and raise body temperature. By reducing prostaglandin production, ibuprofen lowers pain, brings down fever, and reduces swelling and inflammation in affected tissues. In premature infants with a patent ductus arteriosus, lowering prostaglandin levels helps the abnormal blood vessel constrict and close.

Ibuprofen is a racemic mixture — meaning it contains two mirror-image forms of the molecule. The active form is the S-isomer; the inactive R-isomer slowly converts to the active form in the body, acting as a reservoir that helps maintain drug levels over time.

Oral ibuprofen (tablets or liquid-filled capsules) is taken by mouth, typically every 4 to 6 hours as needed. Taking it with food or milk can help reduce stomach upset. Always follow your prescriber's directions or the package label, and use the lowest effective dose for the shortest time needed.

• Caldolor IV (adults and children 3 months+): given by a healthcare provider by IV infusion in a clinical setting; injection vials must be diluted before use, while pre-filled bags are ready to use
• Ibuprofen Lysine IV (premature infants): given in a hospital as a course of three IV doses — an initial dose followed by two more doses at 24-hour intervals

Do not take more than one NSAID at a time, and never exceed the dose on the label or prescribed by your doctor.

The most common side effects with ibuprofen involve the stomach and digestive system:

• Nausea and vomiting
• Gas (flatulence)
• Stomach upset or irritation
• Headache
• Dizziness
• Peripheral edema (leg or ankle swelling)
• With Caldolor IV: infusion site pain, anemia (low red blood cell count)

Serious reactions — including GI bleeding, heart attack, stroke, liver problems, severe skin reactions, and kidney injury — can occur and require immediate medical attention. Stop use and get help right away if you notice black or bloody stools, chest pain, sudden weakness, or severe skin rash.

• Heart attack and stroke risk: All NSAIDs, including ibuprofen, raise the risk of serious and potentially fatal cardiovascular events. This risk can begin early in treatment and grows with higher doses and longer use. Ibuprofen is contraindicated around CABG heart surgery and should be avoided after a recent heart attack unless clearly necessary.
• GI bleeding and ulcers: Ibuprofen can cause stomach or intestinal bleeding, ulcers, and tears — often with no warning symptoms. Risk is highest in older adults, people with a prior ulcer history, alcohol users, smokers, and those on steroids, blood thinners, or aspirin.
• Kidney toxicity: Long-term use or use in people who are dehydrated, elderly, or have kidney or heart problems can reduce blood flow to the kidneys and cause serious kidney damage.
• High blood pressure and heart failure: Ibuprofen can raise blood pressure and worsen heart failure. It may reduce the effectiveness of blood pressure medications including ACE inhibitors, ARBs, beta-blockers, and diuretics.
• Liver toxicity: Rare but serious liver injury has been reported. Watch for nausea, fatigue, jaundice (yellowing of skin or eyes), or upper right belly pain.
• Pregnancy risks: Avoid ibuprofen at around 30 weeks of pregnancy or later — it can cause premature closure of a critical fetal blood vessel. Use between 20–30 weeks should be limited to the lowest dose for the shortest time.
• Serious skin and allergic reactions: Rare but life-threatening skin reactions (Stevens-Johnson Syndrome, toxic epidermal necrolysis) and a severe drug reaction called DRESS have been reported. Stop ibuprofen at the first sign of rash or skin changes.

Ibuprofen interacts with several common medications — tell your doctor and pharmacist about everything you take:

• Warfarin and other blood thinners / antiplatelet drugs: Combined use significantly raises the risk of serious bleeding
• Low-dose aspirin (for heart protection): Ibuprofen can block aspirin's antiplatelet effect; if you take both, timing and formulation matter — ask your pharmacist
• SSRIs and SNRIs (antidepressants): Increased bleeding risk when used with ibuprofen
• ACE inhibitors, ARBs, and beta-blockers: Ibuprofen may reduce their blood pressure-lowering effect and, in vulnerable patients, can cause kidney function to worsen
• Diuretics (water pills): Ibuprofen can blunt the effect of loop and thiazide diuretics
• Digoxin: Ibuprofen can raise digoxin blood levels, increasing the risk of digoxin toxicity
• Lithium: Ibuprofen raises lithium levels in the blood, which can lead to lithium toxicity
• Methotrexate and cyclosporine: Combined use may increase the risk of toxicity from these drugs
• Other NSAIDs or salicylates: Do not take more than one NSAID at a time — it increases GI risk with no added benefit
• Alcohol: Increases the risk of stomach bleeding

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

• Do not use if you have ever had an allergic reaction (including hives, difficulty breathing, or anaphylaxis) to ibuprofen, aspirin, or any other NSAID or pain reliever/fever reducer
• Do not use right before or after coronary artery bypass graft (CABG) heart surgery
• Tell your doctor if you have a history of stomach ulcers, GI bleeding, or peptic ulcer disease — your risk of serious bleeding is greatly increased
• Tell your doctor if you have heart disease, have had a recent heart attack, high blood pressure, or heart failure
• Tell your doctor if you have kidney disease, liver disease, or are dehydrated — ibuprofen can worsen kidney and liver function
• Tell your doctor if you have asthma, especially if aspirin or NSAIDs have ever triggered breathing problems, hives, or nasal polyps — this form of aspirin-sensitive asthma is a contraindication
• Pregnant women should avoid ibuprofen from about 30 weeks onward; use between 20–30 weeks requires a doctor's guidance and monitoring
• Women having difficulty getting pregnant or being evaluated for infertility should talk to their doctor — NSAIDs may reversibly delay ovulation
• Older adults face higher risk for GI, cardiovascular, and kidney side effects — start at the lowest effective dose and monitor closely
• Caldolor is approved for children 3 months and older; safety in infants under 3 months for pain and fever has not been established
• Ibuprofen passes into breast milk in small amounts; discuss with your doctor if you are breastfeeding

Taking too much ibuprofen can cause dizziness, nausea, vomiting, and in serious cases, breathing problems or loss of consciousness — especially in young children. If an overdose is suspected, the stomach may be emptied and activated charcoal may be given to reduce absorption; supportive care and fluids are used as needed.

Contact Poison Control or seek emergency care immediately if you think someone has taken too much ibuprofen, even if they seem okay at first.

Ibuprofen measurably reduces prostaglandin levels in body tissues, which lowers pain sensitivity, reduces fever, and decreases inflammation. In studies of primary dysmenorrhea (painful periods), ibuprofen reduced elevated prostaglandin levels in menstrual fluid and decreased uterine pressure and contraction frequency.

One important pharmacodynamic interaction: ibuprofen can interfere with the antiplatelet (blood-thinning) effect of low-dose aspirin. This interference depends on the dose, timing, and formulation of aspirin — taking ibuprofen before aspirin is more likely to blunt aspirin's effect than taking it afterward.

Oral ibuprofen is rapidly absorbed, with peak blood levels typically reached within 1 to 2 hours of taking a dose. Food can slow the rate of absorption slightly but does not significantly change the total amount absorbed. The elimination half-life — the time it takes for blood levels to fall by half — is approximately 2 to 2.5 hours in adults receiving IV Caldolor, and is shorter in pediatric patients.

Ibuprofen exists as two mirror-image forms (isomers) in the body; the inactive form slowly converts to the active form, acting as an ongoing reservoir of drug. The drug does not accumulate in the body with repeated dosing at recommended intervals.

Store at 20° to 25°C (68° to 77°F) . Avoid excessive heat 40°C (104°F). Dispense in a tight, light-resistant container as defined in the USP.