Paclitaxel
A taxane from the Pacific yew that stabilizes microtubules, used for ovarian, breast and lung cancer and AIDS-related Kaposi sarcoma.
Drug card
- Class
- Taxane
- How it works
- Stabilizing microtubules so they cannot break down and mitosis stalls
- Used for
- Ovarian cancer, first-line with cisplatin or later
- Breast cancer, after surgery or when advanced
- Non-small cell lung cancer, with cisplatin
- AIDS-related Kaposi sarcoma
- Known for
- Neutropenia and other marrow suppression
- Severe hypersensitivity and anaphylaxis
- Peripheral neuropathy
- Its name
- -taxel means a taxane anticancer drug
Study it as a flashcard, and it comes back before you forget it.
Mechanism of action
How does paclitaxel work?
Binds tubulin, promotes microtubule assembly and blocks breakdown, so abnormal bundles form and cells cannot complete mitosis. The standard injection is dissolved in polyoxyl 35 castor oil, and allergy to that vehicle rules it out. CYP2C8 and CYP3A4 metabolize it.
Uses
What is paclitaxel used for?
- Ovarian cancer, first-line with cisplatin or later
- Breast cancer, after surgery or when advanced
- Non-small cell lung cancer, with cisplatin
- AIDS-related Kaposi sarcoma
Side effects
Side effects of paclitaxel
- Neutropenia and other marrow suppressionKnown forSerious
- Severe hypersensitivity and anaphylaxisKnown forSerious
- Peripheral neuropathyKnown forSerious
- Muscle and joint pain
- Hair loss
- Nausea and vomiting
- Diarrhea
- Mucositis
- Low blood pressure during the infusion
- Slow heart rate and conduction blockSerious
- Raised liver enzymes
- Injection site reactions
Known for marks what an exam expects you to know it for.
Watch for
Cautions and what sets it apart
- Premedicate with a corticosteroid, diphenhydramine and an H2 blocker; never rechallenge after a severe reaction.
- Do not give it if neutrophils are too low; repeat cycles only after counts recover.
- Give it before cisplatin: given afterwards, its clearance falls and marrow suppression deepens.
- Use non-PVC bags and sets with an in-line filter, since the solution leaches plasticizer from PVC.
Good to know: An albumin-bound form, not interchangeable with it, is used for breast, lung and pancreatic cancer; premedication is considered only after a past reaction.
Remember it
A way to remember it
Taxanes freeze the scaffold; vincas stop it being built.
Taxanes stabilize microtubules so they cannot be taken apart, while vinca alkaloids prevent them from forming; either way the mitotic spindle fails and the cell cannot divide.
Written for biofideX
Its name
-taxel means taxane anticancer drug
Paclitaxel, docetaxel and cabazitaxel are taxanes. Paclitaxel, from yew trees (Taxus), stabilizes microtubules so they can't break down, which blocks cell division.
- Every drug name stem
Its class
Taxanes
Taxanes, first extracted from yew trees, bind tubulin and push it to assemble into microtubules that then cannot come apart. The over-stable microtubules gather in useless bundles, the mitotic spindle cannot work, and dividing cells stall in mitosis and die. This is the reverse of the vinca alkaloids, which stop microtubules from forming at all.
Easily mixed up with vinca alkaloids.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- Paclitaxel injection: label (DailyMed)
- Paclitaxel protein-bound particles (albumin-bound): label (DailyMed)
- Paclitaxel (NCI Thesaurus)
- Paclitaxel (NCI)
For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.
Cancer chemotherapy
Paclitaxel is one of 9 drugs practiced together here: their classes, how they work, what they treat and what they're known for.
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