What Factors Affect a Sufficient Tranexamic Acid Dose?

Tranexamic acid is a medication that assists the blood clotting process by reducing the activation of plasmin, an enzyme that degrades natural clotting agents like fibrin. There are many factors that affect a tranexamic acid dose used in medicine, including the clinical reason that the medication is being used. Other factors include the kidney function of the patient, body weight, and the way that the drug is administrated.

When this medication is prescribed for heavy menstrual bleeding, the usual tranexamic acid dose is 1,300 milligrams (mg), taken orally with 650 mg tablets. This dose may be taken up to three times a day, for a total of 3,900 mg per day. For this purpose, these dosages are only taken for five days out of every month.

Preventing bleeding in hemophiliac patients having a tooth extraction performed is another common use for this drug. When used in a surgical setting, injection is often used instead of oral tablets, and the tranexamic acid dosage used is 10 mg for every kilogram (kg) that the patient weighs. This dosage may typically be given 2 to 4 times daily for up to 8 days after the surgery.

Both adults and children generally receive similar dosages of this medication when it is used to reduce bleeding during heart disease surgery. The tranexamic acid dose for this purpose is somewhat larger than that for tooth extraction. Initially, the dose is 100 mg per kg of body weight, followed by 10 mg per kg each hour, with another 100 mg per kg given at the beginning of the bypass.

Scoliosis surgery is another situation where this medication can prove useful. This surgery uses a variable loading dose and follow-up dose depending on the doctor's opinion and the severity of the surgery. An initial tranexamic acid dose in this case can range from 10 mg/kg to 100 mg/kg, followed by an hourly infusion of 1 mg/kg up to to 10 mg/kg until the skin closes.

In patients with kidney damage, the tranexamic acid dose often must be reduced. Individuals with serum creatinine levels above 5.7 mg per decaliter (dL) of blood should take half of the usual recommended dosage of this medication. For menstrual bleeding, this would be 650 mg orally, three times a day. In a surgical setting, the medication dosage would be lowered to 5 mg/kg during a tooth extraction. Liver damage does not, however, affect the dosage in any way.