Final answer:
Low DPYD levels can result in higher concentrations of 5-FU in the body, which can increase the risk of toxicity and adverse effects. Individual variations in DPYD activity should be considered when using 5-FU-based therapies.
Step-by-step explanation:
Low DPYD levels can affect 5-FU concentrations by reducing the rate of metabolism of 5-FU. DPYD is an enzyme responsible for breaking down 5-FU in the body. When DPYD levels are low, the clearance of 5-FU decreases, resulting in higher concentrations of 5-FU in the body.
Higher concentrations of 5-FU can lead to an increased risk of toxicity and adverse effects. For example, low DPYD levels have been associated with severe and potentially fatal side effects such as myelosuppression and neurotoxicity in patients treated with 5-FU-based chemotherapy.
It is important to consider DPYD levels and individual variations in DPYD activity when prescribing or administering 5-FU-based therapies to optimize treatment efficacy and minimize the risk of toxicity.