This list includes 49 medications that start with I, ranging from “Ibandronate” to “Ixekizumab.” These drugs include osteoporosis treatments, antibiotics, biologics and immune-modulating medicines commonly used for bone, infection and autoimmune care.
Medications that start with I are generic drug names beginning with the letter I that span many therapeutic areas. A notable example is ibuprofen, an over-the-counter pain reliever recognized worldwide since the 1960s.
Below you’ll find the table with Generic name, Brand name(s), Drug class, Common uses, and Common side effects.
Generic name: The official chemical name used worldwide; use it to search reliably and compare drugs without brand confusion.
Brand name(s): Familiar trade names show how a drug appears in pharmacies and packaging, helping you recognize marketed versions quickly.
Drug class: Indicates the therapeutic category, so you understand related drugs and how they generally act or are prescribed.
Common uses: Short description of typical conditions treated, which helps you spot why a medicine might be considered.
Common side effects: Lists frequent adverse effects so you can watch for symptoms and discuss tolerability with a care provider.
Last updated: September 28, 2025
Medical disclaimer: This information is for general informational purposes and does not replace professional medical advice.
Medications that start with I
| Name | Brand names | Drug class | Typical adult dose (common units) |
|---|---|---|---|
| Ibandronate | Boniva | Bisphosphonate | 150 mg oral once monthly |
| Ibrutinib | Imbruvica | Kinase inhibitor (BTK inhibitor) | 420 mg oral daily |
| Ibuprofen | Advil, Motrin, Nurofen | Nonsteroidal anti-inflammatory drug (NSAID) | 200–400 mg oral every 4–6 hours |
| Ibutilide | Corvert | Class III antiarrhythmic agent | 1 mg IV infusion over 10 minutes |
| Icatibant | Firazyr | Bradykinin B2 receptor antagonist | 30 mg subcutaneous injection as needed |
| Icosapent ethyl | Vascepa | Lipid-regulating agent (omega-3 fatty acid) | 2 g oral twice daily with food |
| Idarubicin | Idamycin PFS | Anthracycline chemotherapy | Varies; e.g., 12 mg/m² IV daily for 3 days |
| Idarucizumab | Praxbind | Antidote, monoclonal antibody | 5 g IV as two separate infusions |
| Idelalisib | Zydelig | Kinase inhibitor (PI3K inhibitor) | 150 mg oral twice daily |
| Ifosfamide | Ifex | Alkylating agent chemotherapy | Varies; e.g., 1.2 g/m² IV daily for 5 days |
| Iloperidone | Fanapt | Atypical antipsychotic | 12–24 mg total oral daily, divided |
| Iloprost | Ventavis, Aurlumyn | Prostaglandin vasodilator | Inhaled 6 to 9 times daily |
| Imatinib | Gleevec | Tyrosine kinase inhibitor | 400 mg or 600 mg oral daily |
| Imiglucerase | Cerezyme | Enzyme replacement therapy | Varies by weight; IV infusion every 2 weeks |
| Imipenem | Primaxin | Carbapenem antibiotic | 500 mg IV every 6 hours |
| Imipramine | Tofranil | Tricyclic antidepressant (TCA) | 75–150 mg oral daily |
| Imiquimod | Aldara, Zyclara | Immune response modifier | Apply 3–5 times per week to affected area |
| Indacaterol | Arcapta Neohaler | Long-acting beta-agonist (LABA) | 75 mcg inhaled once daily |
| Indapamide | Lozol | Thiazide-like diuretic | 1.25–2.5 mg oral daily |
| Indinavir | Crixivan | Protease inhibitor antiviral | 800 mg oral every 8 hours |
| Indomethacin | Indocin, Tivorbex | Nonsteroidal anti-inflammatory drug (NSAID) | 25–50 mg oral 2–3 times daily |
| Infigratinib | Truseltiq | Kinase inhibitor (FGFR inhibitor) | 125 mg oral daily for 21 days of 28-day cycle |
| Infliximab | Remicade, Inflectra, Renflexis | TNF-alpha inhibitor, biologic agent | Varies; e.g., 5 mg/kg IV infusion every 8 weeks |
| Inotuzumab ozogamicin | Besponsa | Antibody-drug conjugate | Varies; IV infusion on a cyclical schedule |
| Interferon alfa-2b | Intron A | Immunomodulator, biologic | Varies widely by indication |
| Interferon beta-1a | Avonex, Rebif | Immunomodulator, biologic | Varies; e.g., 30 mcg IM once weekly |
| Iodixanol | Visipaque | Iodinated contrast medium | Varies by procedure; given IV or intra-arterially |
| Ipratropium | Atrovent HFA | Anticholinergic bronchodilator | 2 inhalations from MDI four times daily |
| Irbesartan | Avapro | Angiotensin II receptor blocker (ARB) | 150–300 mg oral daily |
| Irinotecan | Camptosar | Topoisomerase I inhibitor chemotherapy | Varies; e.g., 125 mg/m² IV weekly |
| Iron Sucrose | Venofer | Iron replacement product | 100–200 mg IV infusion |
| Isavuconazonium | Cresemba | Azole antifungal | 372 mg oral/IV every 8 hours for 6 doses, then daily |
| Isocarboxazid | Marplan | Monoamine oxidase inhibitor (MAOI) | 20–60 mg total oral daily, divided |
| Isoflurane | Forane | Inhaled general anesthetic | Inhaled concentration of 1–2.5% for maintenance |
| Isoniazid | Nydrazid | Antitubercular antibiotic | 300 mg oral daily |
| Isoproterenol | Isuprel | Beta-adrenergic agonist | Varies; e.g., 2–10 mcg/min IV infusion |
| Isosorbide Dinitrate | Isordil | Nitrate vasodilator | 5–40 mg oral 2–3 times daily |
| Isosorbide Mononitrate | Imdur, Monoket | Nitrate vasodilator | 30–120 mg oral once daily (extended-release) |
| Isotretinoin | Accutane, Absorica, Claravis | Retinoid | 0.5–1 mg/kg/day oral, divided in 2 doses |
| Isradipine | DynaCirc CR | Calcium channel blocker | 2.5–10 mg oral daily |
| Istradefylline | Nourianz | Adenosine A2A receptor antagonist | 20–40 mg oral once daily |
| Itraconazole | Sporanox, Onmel | Azole antifungal | 200 mg oral once or twice daily |
| Ivabradine | Corlanor | HCN channel blocker | 5 mg oral twice daily |
| Ivacaftor | Kalydeco | CFTR potentiator | 150 mg oral every 12 hours with fatty food |
| Ivermectin | Stromectol, Sklice | Anthelmintic, antiparasitic | Dose by weight; e.g., 12 mg oral single dose |
| Ivosidenib | Tibsovo | IDH1 inhibitor | 500 mg oral once daily |
| Ixabepilone | Ixempra | Epothilone chemotherapy | 40 mg/m² IV infusion every 3 weeks |
| Ixazomib | Ninlaro | Proteasome inhibitor | 4 mg oral once weekly for 3 of 4 weeks |
| Ixekizumab | Taltz | Interleukin-17A antagonist, biologic | 80 mg subcutaneous injection every 4 weeks |
Descriptions
Ibandronate
A medication used to prevent and treat osteoporosis in postmenopausal women by slowing bone loss. It’s important to take it with a full glass of plain water and remain upright.
Ibrutinib
A targeted therapy used to treat certain types of cancer, such as mantle cell lymphoma and chronic lymphocytic leukemia, by blocking a protein that helps cancer cells grow and survive.
Ibuprofen
A common over-the-counter medication used to relieve pain, reduce fever, and decrease inflammation. Long-term use can increase the risk of stomach bleeding or kidney problems.
Ibutilide
An intravenous medication used in a hospital setting to quickly convert a recent-onset irregular heartbeat (atrial fibrillation) back to a normal rhythm. It requires careful heart monitoring.
Icatibant
A self-injectable medication used for the on-demand treatment of acute attacks of hereditary angioedema (HAE) in adults. It helps relieve swelling and other HAE symptoms.
Icosapent ethyl
A prescription form of an omega-3 fatty acid used with statins to lower high triglyceride levels and reduce the risk of heart attack or stroke in certain high-risk adults.
Idarubicin
A potent chemotherapy drug used in combination with other agents to treat acute myeloid leukemia (AML) by slowing or stopping the growth of cancer cells.
Idarucizumab
An emergency medication that acts as a specific reversal agent for the anticoagulant dabigatran (Pradaxa) when life-threatening or uncontrolled bleeding occurs.
Idelalisib
An oral cancer medication for treating certain types of leukemia and lymphoma, often when other treatments have not worked. It carries a risk of serious side effects.
Ifosfamide
A chemotherapy drug used to treat various cancers, including testicular cancer, by damaging the DNA of cancer cells to prevent them from multiplying.
Iloperidone
An oral medication used for the treatment of schizophrenia in adults. The dose must be increased slowly to minimize side effects like dizziness.
Iloprost
A medication used to treat pulmonary arterial hypertension (PAH) by relaxing blood vessels in the lungs, which lowers pressure and improves symptoms.
Imatinib
A groundbreaking targeted cancer therapy used to treat chronic myeloid leukemia (CML) and certain gastrointestinal tumors by blocking specific proteins that fuel cancer growth.
Imiglucerase
A medication that replaces a missing enzyme in people with Type 1 Gaucher disease, helping to reduce symptoms like an enlarged spleen, liver, and bone abnormalities.
Imipenem
A powerful, broad-spectrum antibiotic used to treat severe bacterial infections. It is always given with cilastatin, which helps it work longer in the body.
Imipramine
An older antidepressant used to treat depression and sometimes childhood bedwetting. It has more side effects than newer antidepressants like SSRIs.
Imiquimod
A topical cream that boosts the body’s immune system to fight certain skin conditions, such as genital warts, superficial skin cancers, and actinic keratosis.
Indacaterol
A long-acting bronchodilator used for the maintenance treatment of chronic obstructive pulmonary disease (COPD) to improve breathing. It is not for sudden breathing problems.
Indapamide
A diuretic (water pill) used to treat high blood pressure and fluid retention (edema) by helping the kidneys remove excess salt and water from the body.
Indinavir
An older antiviral medication used as part of combination therapy to treat HIV infection. Its use has declined due to side effects and complex dosing requirements.
Indomethacin
A potent NSAID used to relieve moderate to severe pain, inflammation, and stiffness associated with conditions like arthritis, gout, and bursitis.
Infigratinib
A targeted therapy used to treat a specific type of bile duct cancer (cholangiocarcinoma) in patients whose tumors have a certain genetic alteration.
Infliximab
A biologic medication given by infusion to treat autoimmune diseases like Crohn’s disease, ulcerative colitis, and rheumatoid arthritis by blocking an inflammatory protein.
Inotuzumab ozogamicin
A targeted chemotherapy drug used to treat relapsed or refractory B-cell acute lymphoblastic leukemia (ALL) by delivering a toxin directly to cancer cells.
Interferon alfa-2b
A man-made protein used to treat conditions like chronic hepatitis C, certain cancers like melanoma, and genital warts by modulating the body’s immune response.
Interferon beta-1a
An injectable medication used to slow disease progression and reduce relapse frequency in people with relapsing forms of multiple sclerosis (MS).
Iodixanol
A diagnostic contrast agent injected into blood vessels to make them and surrounding organs visible on X-ray imaging, such as during a CT scan or angiogram.
Ipratropium
A short-acting bronchodilator used to prevent wheezing, shortness of breath, and chest tightness caused by chronic lung diseases like COPD and asthma.
Irbesartan
A medication used to treat high blood pressure and protect the kidneys from damage due to diabetes by relaxing blood vessels so that blood can flow more easily.
Irinotecan
A chemotherapy drug primarily used to treat advanced colorectal cancer. A common side effect is severe diarrhea, which requires careful management.
Iron Sucrose
An intravenous iron formulation used to treat iron-deficiency anemia in people with chronic kidney disease who cannot take oral iron or for whom it is not effective enough.
Isavuconazonium
An antifungal medication used to treat serious, invasive fungal infections like aspergillosis and mucormycosis, particularly in patients with weakened immune systems.
Isocarboxazid
An older antidepressant for treatment-resistant depression. It requires strict dietary restrictions (avoiding tyramine-rich foods) to prevent dangerous high blood pressure.
Isoflurane
An inhaled gas used by anesthesiologists to induce and maintain general anesthesia during surgery. It produces a state of unconsciousness and immobility.
Isoniazid
A primary antibiotic used in combination with other drugs to treat and prevent active and latent tuberculosis (TB) infections. It can affect the liver and nerves.
Isoproterenol
A potent heart-stimulating medication used in hospital settings to treat very slow heart rates (bradycardia), heart block, and certain types of shock.
Isosorbide Dinitrate
A medication used to prevent and treat chest pain (angina) caused by heart disease. It works by relaxing and widening blood vessels to improve blood flow to the heart.
Isosorbide Mononitrate
A long-acting nitrate used to prevent angina (chest pain). It is a more modern version of isosorbide dinitrate with more predictable effects and simpler dosing.
Isotretinoin
A powerful oral medication for treating severe, scarring acne that has not responded to other treatments. It has a high risk of causing severe birth defects if taken during pregnancy.
Isradipine
A medication used to treat high blood pressure (hypertension). It works by relaxing blood vessels, which lowers blood pressure and makes it easier for the heart to pump blood.
Istradefylline
An add-on treatment for adults with Parkinson’s disease who are experiencing “off” episodes, where symptoms return between doses of levodopa/carbidopa.
Itraconazole
An oral antifungal used to treat a wide variety of fungal infections, including those affecting the lungs, nails, and other parts of the body. Can interact with many other drugs.
Ivabradine
A heart medication used to reduce the risk of hospitalization for worsening heart failure in certain patients. It works by specifically slowing the heart rate.
Ivacaftor
A targeted therapy for cystic fibrosis (CF) in patients with specific genetic mutations. It helps a faulty protein at the cell surface work better, improving CF symptoms.
Ivermectin
An antiparasitic drug used to treat infections caused by roundworms and other parasites, as well as topical treatments for head lice and rosacea.
Ivosidenib
A targeted cancer therapy used to treat acute myeloid leukemia (AML) and bile duct cancer (cholangiocarcinoma) that have a specific mutation in the IDH1 gene.
Ixabepilone
A chemotherapy drug used to treat advanced or metastatic breast cancer, often after other chemotherapy treatments have failed. It works by stopping cancer cell division.
Ixazomib
An oral medication used in combination with other drugs to treat multiple myeloma, a type of blood cancer. It must be taken on an empty stomach.
Ixekizumab
An injectable biologic medication used to treat moderate to severe plaque psoriasis, psoriatic arthritis, and certain types of spondyloarthritis by targeting a specific inflammatory protein.