Tranexamic Acid USP (API Powder)

Tranexamic acid (TXA) is a synthetic analog of the amino acid lysine used as an antifibrinolytic agent. In its raw form (USP grade), it is a white or nearly-white crystalline powder (CAS No. 1197-18-8). It is highly soluble in water and must be compounded (mixed with excipients) by a pharmacist to make dosage forms (tablets, injections, oral solutions). The “USP” designation means the powder meets United States Pharmacopeia standards for purity, strength and identity.

Tranexamic Acid API Pure Powder USP refers to the pure, active pharmaceutical ingredient (API) form of tranexamic acid that meets the quality and purity standards set by the United States Pharmacopeia (USP).

What is Tranexamic Acid?

• Tranexamic acid is a synthetic derivative of the amino acid lysine.
• It is classified as an antifibrinolytic agent, meaning it helps prevent the breakdown of blood clots.
• Tranexamic acid inhibits the activation of plasminogen to plasmin, thereby reducing bleeding.

Mechanism of Action

Tranexamic acid works by inhibiting fibrinolysis. It reversibly binds to plasminogen’s lysine-binding sites, preventing its conversion to plasmin (the enzyme that degrades fibrin clots). In effect, TXA “stabilizes” formed clots and prevents excess bleeding. Unlike anticoagulants, it does not stop clot formation – it merely slows clot breakdown, preserving native hemostatic clots. (At high concentrations it may also directly inhibit plasmin activity.) Pharmacologically, TXA is classified as an antifibrinolytic. By blocking plasmin(ogen), it reduces bleeding from mucosal surfaces and injury sites.

Pharmacokinetics

• Absorption: Orally, TXA is well-absorbed (bioavailability ~~33–50% in adults); peak blood levels occur in ~2–3 hours. It can be taken with or without food.
• Distribution: It distributes into tissues and crosses the placenta; only small amounts enter breast milk (≈1% of maternal plasma levels).
• Metabolism/Excretion: Almost no hepatic metabolism: TXA is eliminated primarily unchanged by the kidneys (glomerular filtration). About 90–95% of a dose is excreted in urine within 24 h (Because of this, dose reduction is required in renal impairment.) Minimal byproducts are formed, so it has low liver burden. Its plasma half-life is ~2–3 hours. (No special monitoring is needed usually, aside from renal function.)

Clinical Uses (Indications)

Tranexamic acid is used to treat or prevent excessive hemorrhage in a variety of settings. Key approved or customary uses include:

• Menorrhagia (Heavy Menstrual Bleeding): TXA tablets are FDA-indicated for cyclic heavy menstrual bleeding (menorrhagia) in women of reproductive age. A typical regimen is 1300 mg orally three times daily (3900 mg/day) for up to 5 days each menstrual cycle. This reduces menstrual blood loss by stabilizing clots in the uterine lining.
• Obstetric Bleeding (Postpartum Hemorrhage): TXA (1–2 g IV) is now widely used off-label in postpartum hemorrhage (PPH). Early administration (ideally within 3 hours of delivery) significantly reduces maternal death from bleeding. The World Health Organization recommends early IV TXA in PPH. (The mountainside medical summary notes TXA is used to treat excessive bleeding in conditions like “postpartum hemorrhage”.)
• Surgical/Trauma Bleeding: Intraoperatively and in trauma, TXA (IV) is used to minimize blood loss. For example, in major orthopedic, cardiac and trauma surgeries, a 1 g IV dose (often followed by additional dosing) is common to reduce transfusions. The drug’s clot-stabilizing effect helps control surgical bleeding. (In acute trauma, the CRASH-2 trial showed that giving TXA within 3 hours reduced mortality.)
• Hereditary Angioedema and Bleeding Disorders: TXA is used as an adjunct in hereditary angioedema to reduce bradykinin-mediated swelling, and in hemophilia or von Willebrand disease to control mucosal or surgical bleeding. For example, TXA mouthwashes or mouth tablets help prevent bleeding after tooth extraction in hemophilia.
• Dentistry/Nosebleeds: A 4–5% TXA mouthwash or toner (e.g. soak gauze in solution) is used to control oral bleeding after dental procedures (especially in anticoagulated patients). It is also used as nasal spray (or soaked tampons) for refractory epistaxis.
• Dermatology (Melasma): TXA has a beneficial effect in reducing melanin production. Orally or topically, it can help lighten melasma (brown facial spots) and other hyperpigmentation. (This use is off-label but increasingly common in dermatology.)
• Other: TXA may be used in GI bleeding, hematuria, and other hemorrhagic conditions, though evidence varies.

TXA is primarily indicated for bleeding control: heavy menstrual bleeding and bleeding associated with surgery, trauma, or coagulopathies. (It is not used on its own to stop active clots, but to augment clot strength.) The US injectable product is FDA-indicated for short-term use in hemophilia patients (before/during dental extraction), but practitioners widely use the solution in other bleeding situations. Notably, TXA must be prescribed – it is not available OTC. The API powder is only supplied to compounding pharmacies for use in prescription formulations.

Dosage Forms and Administration

Tranexamic acid API powder is formulated into the following dosage forms:

• Oral tablets/capsules: Common strengths are 650 mg or 1000 mg (by combination). The usual oral dose for menorrhagia or other indications is 25–50 mg/kg per day (up to ~3900 mg/day) in divided doses (dailymed.nlm.nih.gov). A typical adult regimen is 1300 mg PO TID for 3–5 days. For elderly or low body weight, adjust accordingly. Tablets should be swallowed whole.
• Intravenous injection/infusion: The standard IV form is 100 mg/mL (10 mL vials of 1000 mg) (dailymed.nlm.nih.gov). A common IV dose in acute bleeding is 1 gram, infused over 10 minutes. Dosing can be repeated once (for a total of 2 g) or given as a slow infusion (e.g. 1 g over 8 hours) depending on bleeding severity. For hemophilia (per label): 10 mg/kg IV as one dose before a procedure, repeating 3–4 times daily for 2–8 days (dailymed.nlm.nih.gov). (Doses >100 mg/minute may cause hypotension.) ALWAYS ensure IV route – Never give TXA intrathecally (it causes seizures (dailymed.nlm.nih.gov)).
• Topical solutions: A 5–10% aqueous solution (e.g. 500 mg in 10 mL saline) can be applied locally (mouth rinse, soaked dressing) to control bleeding. This requires compounding.
• Nasal spray: Commercial 10% TXA nasal sprays exist. (Compounded spray can be made from the powder in glycerin/water.)
• Postpartum/trauma protocols: In obstetrics or trauma, hospitals often stock 10 mL vials (1000 mg) of IV TXA. The protocol may be 1 g IV as soon as hemorrhage is diagnosed.

Because TXA is primarily renally excreted, renal dosing adjustments are required. For example, if serum creatinine >1.4 mg/dL, reduce frequency (Menstrual bleeding regimen: see label). (Tablets: 1300 mg BID or daily instead of TID, per creatinine levels.) There are no dosage adjustments for mild hepatic impairment, as TXA is not metabolized by the liver.

Compounding note: The API powder is used to make these formulations. It must be reconstituted and buffered properly (e.g. pH ~6–8) for injections. The final pH is usually slightly acidic. Practitioners should not attempt to dose the powder directly – it is for pharmacist use only.

Contraindications and Precautions

• Thromboembolic disease: TXA is contraindicated in patients with active intravascular clotting or a history of thrombosis (DVT, PE, stroke). Do not use in patients with known hypercoagulable states. (TXA reduces clot breakdown, so it can worsen or precipitate thromboses.) Diabetics, smokers, or those on high-dose estrogen pills should use cautiously.
• Subarachnoid hemorrhage: Contraindicated — TXA can cause cerebral edema and infarction in SAH. IV TXA is not used for head injury bleeds. (Meningeal irritation/seizures can occur.)
• Hypersensitivity: Contraindicated if the patient has had an allergic reaction to TXA or its formulations. Tinctorial (skin) ingredients and parabens can also trigger allergy. Signs of anaphylaxis warrant immediate discontinuation.
• Ocular factors: Use caution in patients with active retinal, ophthalmic vessel, or vitreous bleeding. (Retinal vein/artery occlusion has been reported with TXA, especially in those on birth control.) If the patient experiences blurred vision or eye pain, TXA should be stopped and ophthalmology consulted.
• Pregnancy: Before delivery, TXA tablets are not indicated for use in pregnant women (no controlled studies exist). It crosses the placenta, so routine use in pregnancy is avoided except for life-threatening postpartum hemorrhage (after delivery). No teratogenic effects were seen in animal studies at clinical doses, but caution is advised.
• Breastfeeding: TXA is excreted in breast milk (~1% of serum levels). The risk to the infant is presumed low, but a decision should consider the nursing benefits. If maternal TXA is needed (e.g. PPH control after birth), breastfeeding may be paused for 12–24 hours.
• Renal impairment: Because TXA is renally cleared, reduce dose if creatinine is elevated (e.g. give 2g/day instead of 4g, or extend interval). Monitor renal function in prolonged therapy.
• Contraindicated drug interactions: Avoid concurrent use of TXA with blood-clotting factor concentrates (e.g. Factor IX complex or anti-inhibitor coagulant) or etretinate/retinoids, as these combinations can severely increase thrombosis risk. Also, do not give TXA with systemic fibrinolytics (tPA, streptokinase) (they work oppositely). Concomitant hormonal contraceptives or high estrogen therapy may increase clot risk with TXA.
• Route precautions: For the injection form, confirm IV route. Intrathecal/spinal injection of TXA causes seizures and neurotoxicity, so it must never be given into the epidural or spinal space. When administering an IV bolus, infuse slowly (over ≥10 min) to avoid hypotension.
• Side effects: Common adverse effects are usually mild: gastrointestinal upset (nausea, diarrhea), headache, back or muscle pain, and fatigue. Less common are hypotension (if injected too fast), muscle cramps, vision changes, or allergic rash. Seizures can occur rarely at high IV doses (especially in renal failure) – this risk underlies the recommendation against neuraxial use.
• Monitoring: Generally no lab monitoring is required except renal function. Stop TXA if signs of thrombosis appear (leg swelling/pain, chest pain, neurological deficits). If used for >5 days, monitor vision and blood counts (anemia/fibrinogen not directly affected, but assess overall).

Special Populations and Tips

• Geriatrics: Avoid use in elderly unless clear indication, due to higher thrombotic risk. No dosage adjustment is specifically recommended besides renal dosing.
• Pediatrics: TXA is used in children (e.g. congenital bleeding disorders, surgery) at weight-based doses (10–25 mg/kg). Pharmacy should verify pediatric dosing.
• Counseling and Nursing Tips: Explain that TXA is for bleeding control, not a pain reliever. Advise patients that it may cause minor GI upset and to take with food if needed. Reinforce adherence to dosing times during heavy bleeding episodes. Educate women that TXA will not stop menstrual flow immediately but will reduce total blood loss.
• Concomitant Care: Treat underlying causes of bleeding concurrently (e.g. mechanical controls for PPH, iron supplementation for anemia, ect.). In PPH, TXA is an adjunct to uterotonics (oxytocin), uterine massage, and surgical interventions as needed. In menorrhagia, combine TXA with other management (hormonal therapy, iron therapy).

What Does API Pure Powder Mean?

• API (Active Pharmaceutical Ingredient): This is the primary, pharmacologically active compound used to make finished drugs.
• Pure Powder: The raw, unformulated, highly purified powder (almost 100% tranexamic acid), suitable for pharmaceutical manufacturing.
• This is not the finished medicine but the raw material used to prepare medications (tablets, capsules, injections).

What Does USP Mean?

• USP stands for United States Pharmacopeia.
• If a product is labeled "USP," it meets rigorous quality, purity, strength, and identity standards set by the USP.
• This means the powder's chemical composition, potency, and absence of impurities have been verified according to USP specifications.

Uses of Tranexamic Acid API Pure Powder USP

• Making prescription medications for:
  • Heavy menstrual bleeding (menorrhagia)
  • Surgical procedures to minimize blood loss
  • Hereditary angioedema and other rare bleeding disorders
  • Sometimes used topically or orally for melasma (skin hyperpigmentation) in dermatology

Tranexamic Acid USP for compounding is a medication used for the treatment or prevention of excessive bleeding or hemorrhage. It is commonly used during surgeries, dental procedures, and for heavy menstrual bleeding. Tranexamic Acid works by preventing the breakdown of blood clots, thereby reducing bleeding. It is also used as an antifibrinolytic agent to treat conditions such as hemophilia and von Willebrand disease. This medication is only available for compounding, which means it is not a commercially available product and must be prepared by a licensed pharmacist according to a specific formula prescribed by a healthcare provider. 

Tranexamic acid USP is an active pharmaceutical ingredient (API) used in prescription medications. It belongs to the class of drugs called antifibrinolytics, which work by preventing the breakdown of blood clots in the body.

Tranexamic acid USP is primarily used to prevent or treat excessive bleeding in patients with certain medical conditions, such as bleeding disorders, heavy menstrual bleeding, and postpartum hemorrhage. It is also used in dentistry and in surgeries to reduce bleeding.

Tranexamic acid USP is a synthetic form of the amino acid lysine and is available in various forms such as tablets, injections, and nasal sprays. It works by blocking the activity of plasmin, an enzyme responsible for breaking down blood clots. This helps to maintain normal blood clotting and control bleeding.

As an API, tranexamic acid USP is subject to strict quality control measures and must meet specific criteria for purity, strength, potency, and stability set by the USP. It is approved by the US Food and Drug Administration (FDA) and is considered safe and effective when used as directed by a healthcare professional.

CAS Number: 1197-18-8

Tranexamic acid USP powder is a potent antifibrinolytic API used to compound medications that prevent or treat bleeding. It is chemically a lysine analog that blocks plasmin and stabilizes clots. Clinically, TXA is invaluable in heavy menstrual bleeding, perioperative hemorrhage, and obstetric bleeding. Its shelf-life is long, but it must be formulated into patient-ready dosage forms. When using or prescribing TXA, clinicians should be aware of its dosing (e.g. 1300 mg PO TID in menorrhagia), renal elimination, and key contraindications (active clots, subarachnoid bleeding, allergies). Monitoring is straightforward, but nurses should observe for any signs of thrombosis or visual disturbance. By following dosing guidelines and precautions, TXA can markedly reduce bleeding without major systemic toxicity.