Genotype 1b is a strain of the hepatitis C virus that causes a patient to develop hepatitis C, according to the U.S. Department of Veterans Affairs. As of 2015, genotype 1 is the most common genotype for Americans diagnosed with hepatitis C and is comprised of subtypes 1a and 1b.
Genotypes are defined by genetic groups and diagnosed through blood tests, states the U.S. Department of Veterans Affairs. Generally, a patient only has one genotype. While it does not play a significant role in the progression of liver disease as a result of hepatitis, the diagnosis of the genotype is an important factor in determining the length and method of treatment. Genotype 1 is harder to treat, and the process is often longer with patients receiving 48 weeks of treatment compared to patients with genotypes 2 and 3 who receive 24 weeks.
Standard treatment for genotypes 1, 2 and 3 include medications such as ribavirin, interferon and an antiviral drug, according to Everyday Health. As of January 2014, a relatively new treatment known as Sovaldi may also be prescribed. Studies have shown Sovaldi to have a higher success rate in the treatment of hepatitis C, a chronic disease that causes death in many cases. Depending on the type of treatment prescribed, side effects may include rash, insomnia, dizziness, fatigue and anemia.