Medically reviewed by A Ras MD.
What is pirfenidone used for?
Pirfenidone is a prescription medicine that is used to treat idiopathic pulmonary fibrosis.
Pirfenidone belongs to the chemical class of pyridone. Pirfenidone capsules are available as a opaque white to off-white hard gelatin capsule containing 267 mg of pirfenidone for oral administration.
Pirfenidone has a molecular formula of C12H11NO and a molecular weight of 185.22 g/mol. Pirfenidone has the following structural formula, which has been referred to as 5-methyl-1-phenylpyridin-2-one.
Pirfenidone is a white to pale yellow, non-hygroscopic, crystalline powder. It is sparingly soluble in water, freely soluble in ethanol (96%), and slightly soluble in heptane. The melting point range is 107°C to 111°C.
Each pirfenidone capsule contains pirfenidone, 267 mg as active ingredient and the following inactive ingredients: croscarmellose sodium, hypromellose, lactose monohydrate, and magnesium stearate. In addition, the capsule shell contains gelatin and titanium dioxide.
The capsule is imprinted with black pharmaceutical ink which includes butyl alcohol, dehydrated alcohol, ferrosoferric oxide, isopropyl alcohol, potassium hydroxide, propylene glycol, purified water, shellac, and strong ammonia solution.
Mechanism of Action
The mechanism of action of pirfenidone in the treatment of IPF has not been established.
Before taking pirfenidone, tell your doctor:
- If you are allergic to pirfenidone; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have any of these health problems: Kidney disease or liver disease.
- If you are taking any drugs that may make your skin more sensitive to light. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
This is not a list of all drugs or health problems that interact with pirfenidone.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take pirfenidone with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take pirfenidone?
- Tell all of your health care providers that you take pirfenidone. This includes your doctors, nurses, pharmacists, and dentists.
- You may get sunburned more easily. Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun.
- Stop smoking before starting pirfenidone. Avoid smoking while taking it. Smoking may lower how well pirfenidone works. Talk with your doctor.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
How is pirfenidone best taken?
Use pirfenidone as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take pirfenidone with food.
- Take pirfenidone at the same time of day.
- Keep taking pirfenidone as you have been told by your doctor or other health care provider, even if you feel well.
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it, with food.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
- If you miss 14 or more days of taking pirfenidone, call your doctor before you start taking it again.
What are the side effects of pirfenidone that I need to call my doctor about immediately?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Chest pain or pressure.
- Any unexplained bruising or bleeding.
- Liver problems have rarely happened with pirfenidone. Sometimes, this has been deadly. Call your doctor right away if you have signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
What are some other side effects of pirfenidone?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Feeling dizzy, tired, or weak.
- Signs of a common cold.
- Joint pain.
- Change in taste.
- Trouble sleeping.
- Weight loss.
- Stomach pain or heartburn.
- Diarrhea, throwing up, upset stomach, and feeling less hungry are common with pirfenidone. If these happen, talk with your doctor about ways to lower these side effects. Call your doctor right away if any of these effects bother you, do not get better, or get very bad.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
If overdose is suspected:
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
How do I store and/or throw out pirfenidone?
- Store at room temperature.
- Store in a dry place. Do not store in a bathroom.
- Keep lid tightly closed.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
PRINCIPAL DISPLAY PANEL
- NDC 60219-1642-7
- Pirfenidone Capsules, 267 mg
- 270 Capsules
- Rx only
- Amneal Pharmaceuticals LLC
SRC: NLM .