Everything we eat, drink, breathe, smoke, inject and apply to the skin passes through the liver. The liver processes everything it can, and tries to eliminate or metabolize potentially harmful substances, such as drugs or alcohol. If a substance is toxic, or if there is too much of it, the liver can become overburdened. This is particularly true about alcohol and drugs, whether prescription, nonprescription, or illicit. Smoking cigarettes or marijuana may also harm the liver, especially if you have hepatitis C. The use of drugs and alcohol during sex is associated with increased hep C transmission.

To protect your liver, try to avoid all alcohol use if you have hepatitis C. Research shows that alcohol increases HCV replication, promotes damage to the liver and increases the likelihood of developing cirrhosis. Alcohol acts like fertilizer to hepatitis C. Even moderate amounts of alcohol may increase your risk of fibrosis

If you are on hep C treatment, it’s especially important to avoid alcohol. The goal of treatment is to stop the hepatitis C from replicating, and drinking alcohol has the opposite effect. If you can’t or don’t want to stop drinking, try to limit your alcohol intake. The U.S. Department of Agriculture and U.S. Department of Health and Human Services’ Dietary Guidelines for Americans 2010 for moderate alcohol consumption is one drink per day for women and two drinks per day for men. The size of standard drinks depends on what you are drinking:

  • 12 ounces of regular beer, which is usually about 5 percent alcohol
  • 5 ounces of wine, which is typically about 12 percent alcohol
  • 1.5 ounces of distilled spirits, which is about 40 percent alcohol

Binge drinking is especially harmful to the liver, so not drinking during the week so you can drink more on the weekends is risky. If stopping or reducing alcohol is a goal for you but you find it difficult to do, ask your doctor for help.

You may wonder if you can drink after successful hepatitis C treatment. If you have cirrhosis or advanced fibrosis, continue to abstain. If you had minimal liver damage prior to treatment, there isn’t good research on this yet, so experts tend to advise against alcohol consumption. The thinking behind this is that it took a lot to cure hepatitis C, so it makes sense to do everything you can to protect your liver. Some doctors say it is all right to have a drink when the occasion is special, such as at the wedding of a family member. If you’d like to drink, talk to your health care provider about this.

In addition to harming the liver, drug use has the additional problem of increasing hepatitis C transmission risk. People who inject drugs are at high risk for hep C. Anything used in the process of preparing and injecting drugs may be a vehicle for spreading HCV, including syringes, cookers, cotton filters, preparation water, the surface on which the drug is prepared, and the drug itself. Disinfecting needles and syringes with bleach or alcohol has not been proven to prevent HCV transmission.

Inhaling drugs may also transmit hep C via tiny droplets of blood passed on straws. The nasal passages break easily, particularly when they are dry. There is also a remote risk of passing hepatitis C through mouth sores, chapped lips or bleeding gums when sharing items like crack pipes.

To reduce risk of contracting or transmitting HCV and to protect the liver, consider stopping illicit drug use. Treatment programs can help with this. If you do continue to use, some ways that may reduce your risk are:

  • Don’t share needles, syringes, water or drug preparation equipment.
  • Only use needles, syringes and other equipment that was new and obtained from a reliable source, such as a pharmacy or needle-exchange program.
  • Be sure the surface you are preparing drugs on is clean and has not been exposed to hep C.
  • Use clean water from a reliable source (bottled or fresh tap water) and from a container that has not held previously contaminated water.
  • Use a new cooker and filter to prepare drugs.
  • Safely dispose of syringes so that others are not harmed.


Smokers with hepatitis C have a higher rate of liver cancer than nonsmokers. Recent research using mice found that nicotine aerosol (vaping) demonstrated profound adverse effects on the liver.

Switching to vaping may be less harmful than continuing to smoke, but a growing body of evidence shows that using aerosolized nicotine is hazardous too. Quitting nicotine is always a good idea, but stopping can be hard. If you are interested in quitting nicotine, talk to your health care provider.

Last Reviewed: July 15, 2019