Paclitaxel is given as a shot to the vein (intraveneously). An experienced physician should supervise administraction, although a nurse or technician often sticks the tube in the blood vessel. It takes a while for the drug to enter the circulatory system, so the patient is hooked up for over 30 minutes. The time for treatment varies considerably for different patients and different cancers. Sometimes it takes hours to administer the Paclitaxel.
Because Taxol is a toxin, healthcare providers use gloves. Topical exposures have resulted in tingling, burning and redness.
The website uptodate.com reports these typical dosages
Ovarian carcinoma:
I.V.: 135-175 mg/m2 over 3 hours every 3 weeks or
135 mg/m2 over 24 hours every 3 weeks or
50-80 mg/m2 over 1-3 hours weekly or
1.4-4 mg/m2/day continuous infusion for 14 days every 4 weeks
Intraperitoneal (unlabeled route): 60 mg/m2 on day 8 of a 21-day treatment
cycle for 6 cycles, in combination with I.V. paclitaxel and intraperitoneal
cisplatin. Note: Administration of intraperitoneal paclitaxel should include
the standard paclitaxel premedication regimen.
Metastatic breast cancer:
I.V.: 175-250 mg/m2 over 3 hours every 3 weeks or
50-80 mg/m2 weekly or
1.4-4 mg/m2/day continuous infusion for 14 days every 4 weeks
Nonsmall cell lung carcinoma:
I.V.: 135 mg/m2 over 24 hours every 3 weeks
AIDS-related Kaposi's sarcoma:
I.V.: 135 mg/m2 over 3 hours every 3 weeks
or 100 mg/m2 over 3 hours every 2 weeks
Clinical trials resulted in unprecedented success in treating ovarian cancer. Taxol had become a miracle drug. The sudden demand for Yew bark led to illegal “Taxus Rustling” and legal cottage industries. These new jobs were seen locally as replacements to the declining timber industry. It was obvious to everyone that the demand was unsustainable. Although complete synthesis of Taxol was successful, it was not practical. A process that creates the precursors by plant cell fermentation is now used to produce the world’s supply of Taxol. By 1995, all dependence upon the Pacific Yew was eliminated.
The popularity of this effective drug made it a “blockbuster”. Bristol Meyers Squibb sales of their branded product, Taxol, were almost $1.6 billion in 2000. There were numerous patents for various applications, which began to run out in the late 1990’s. The generic equivalent, Onxol, came on the market in 2000 and accounted for 17% of Ivax total generic sales in 2001.
Undoubtedly, there are numerous agents to be discovered from plant,
marine, and fungal sources that will have therapeutic value. Cancer is
not one disease. It is several hundred diseases and will need continued
search for agents to treat them. Thus, Taxol has demonstrated the utility
of searching for highly active natural products. It was a successful business
venture as well as a medical success, saving many lives.
Paclitaxel is administered as part of a liquid solution. It's dissolved in polyoxyethylated castor oil (often a branded solvent called Cremophor) and ethanol. Strictly speaking, Taxol refers to the solution rather than the Paclitaxel itself. The side effects of Paclitaxel, like those of many agents, is due to systematic administration - the drug travels through the bloodstream to the whole body and it stops fast-mulitplying cells in the hair follicles and intestines (resulting in hair loss and nausea.)
Taxol has another downside that other chemo agents don't have in that the cremophor and alcohol are toxic. It also does not work well with a range of other medicines. Consult your healthcare provider before starting any new medicine, including over-the-counter products.
Elimination
Paclitaxel exits the body mostly through the feces. Less than 20% comes out in the urine. For a 3-hour administration, the half-life is under 24 hours.