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Disponible en español: Qué Are PARP Inhibitors?

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What Are PARP Inhibitors?

PARP inhibitors: what the regimen or drug class includes, why it is used, and what to ask.

This is general education — it cannot tell you what to do in your situation.

Instructions and urgent-contact thresholds vary by treatment and care team. If you are in treatment, follow the instructions your oncology team gave you, and contact them about any new or worsening symptom. If you think you may be having a medical emergency, call your local emergency number.

AI-assisted and source verified. Not reviewed by a healthcare professional unless specifically stated.

Sources last checked: 2026-07-20Last updated: 2026-07-20Next planned review: 2027-01-16

How this page was created

Cancer Explained uses AI to organize and translate information from the authoritative sources cited on each page. Automated checks review claims, citations, clarity, duplication, and potential safety concerns before publication. Our content is not currently reviewed by physicians unless a specific qualified reviewer is named on the page. Cancer Explained provides general education and should not replace advice from your healthcare team.

Editorial status — Editorial review complete. This page completed Cancer Explained's editorial checks (sources, safety, plain language, duplication). It has not been reviewed by a physician or other healthcare professional.

High-risk topic — talk to your care team. This topic can involve urgent, individual medical decisions. This page is general education only: it cannot tell you whether your situation is an emergency or what you personally should do. Follow your oncology team's instructions and contact them for individual guidance.

Human medical review: not completed. At this time, most Cancer Explained content has not been reviewed by a physician or other healthcare professional. Pages with documented human medical review identify the reviewer, credentials, and review date directly.

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NCI source

National Cancer Institute - Definition of PARP Inhibitor

Visual summary for What Are PARP Inhibitors?

The short answer

PARP inhibitors is a cancer treatment name people often see in a portal, consent form, or infusion schedule. It includes targeted medicines that block PARP, an enzyme involved in DNA repair and may be used for selected ovarian, breast, prostate, pancreatic, and other cancers depending on biomarkers and approval context. This guide explains the name, schedule questions, side effects, and decision points.

  • PARP inhibitors is a treatment name, not a whole treatment plan by itself.

  • It includes targeted medicines that block PARP, an enzyme involved in DNA repair.

  • It may be used for selected ovarian, breast, prostate, pancreatic, and other cancers depending on biomarkers and approval context.

  • Dose, schedule, monitoring, and supportive medicines are individualized by the oncology team.

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The full explanation.

The short answer

PARP inhibitors is a cancer treatment name. It includes targeted medicines that block PARP, an enzyme involved in DNA repair. It may be used for selected ovarian, breast, prostate, pancreatic, and other cancers depending on biomarkers and approval context, but whether it fits depends on the exact cancer, stage, biomarkers, prior treatment, overall health, and treatment goal.

What the name means

Regimen names are shorthand. They help oncology teams communicate quickly, but they do not tell you the dose, number of cycles, infusion length, anti-nausea plan, lab schedule, or how the regimen fits with surgery, radiation, immunotherapy, or targeted therapy.

How it is usually given

PARP inhibitors is usually oral targeted therapy, with monitoring for blood counts and other side effects. Ask for a calendar that shows infusion days, home medicines, lab checks, scans, and when side effects tend to peak.

Why your team might choose it

Your team may consider PARP inhibitors because evidence supports it in certain cancer settings, because it matches the treatment goal, or because it balances benefit and side effects better than another option. Ask what alternatives were considered.

Side effects to discuss before day one

Do not wait until treatment starts to ask about side effects. Ask which effects are common, which are serious, which can be prevented, and which require same-day contact. Also ask who to call after hours and what number to use.

How response is checked

Response may be checked with symptoms, physical exam, blood tests, tumor markers, imaging, pathology after surgery, or a mix of these. Ask when the first response check happens and what would count as working, stable, or not working.

Practical planning

Before the first cycle, ask about transportation, work time, infection precautions, eating and hydration, mouth care, fertility, sexual health, vaccines, dental work, and medication interactions. The practical details are part of the treatment plan.

Related pages

Start with Chemotherapy, Cancer Treatment Overview, Questions Before Chemo, and Side Effects of Cancer Treatment.

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Common questions

What is PARP inhibitors?

PARP inhibitors includes targeted medicines that block PARP, an enzyme involved in DNA repair.

What cancers is PARP inhibitors used for?

It may be used for selected ovarian, breast, prostate, pancreatic, and other cancers depending on biomarkers and approval context.

What should I ask before starting?

Ask about the goal of treatment, schedule, side effects to report, medicines to take at home, and how response will be checked.

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0 of 3 answered

  1. Q1.What is a regimen?
  2. Q2.What should you ask before starting a regimen?
  3. Q3.Why can two people receive different schedules?

This quiz checks understanding of educational content only. It is not medical advice. Open this quiz on its own page.

How this page was created

Cancer Explained uses AI to organize and translate information from the authoritative sources cited on each page. Automated checks review claims, citations, clarity, duplication, and potential safety concerns before publication. Our content is not currently reviewed by physicians unless a specific qualified reviewer is named on the page. Cancer Explained provides general education and should not replace advice from your healthcare team.

Editorial status: Editorial review complete This page completed Cancer Explained's editorial checks (sources, safety, plain language, duplication). It has not been reviewed by a physician or other healthcare professional.

Human medical review: not completed. At this time, most Cancer Explained content has not been reviewed by a physician or other healthcare professional. Pages with documented human medical review identify the reviewer, credentials, and review date directly.

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What Are PARP Inhibitors?