Drug Interactions between 5-hydroxytryptophan / melatonin / pyridoxine and olaparib

Do not consume grapefruit, grapefruit juice, or Seville oranges during treatment with olaparib. Doing so can significantly increase the blood levels of olaparib and increase the risk and/or severity of side effects such as nausea, vomiting, diarrhea, indigestion, loss of appetite, abdominal pain or discomfort, lung problems, and impaired bone marrow function resulting in low numbers of different types of blood cells. You may also be more likely to develop anemia, bleeding problems, or infections due to low blood cell counts. Talk to your doctor if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Both smoking and excessive caffeine consumption can alter the blood levels of melatonin, which may affect the dosing. Tobacco smoking reduces, while caffeine increases melatonin blood levels. If you start smoking or undergo smoking cessation, your doctor may need to adjust the dose of melatonin. In addition, alcohol may reduce the effect of melatonin on sleep. It is best to avoid alcohol consumption during melatonin therapy. Talk to a healthcare professional if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.