Drug Interactions between lonafarnib and oxytetracycline / phenazopyridine / sulfamethizole

Lonafarnib should be taken with the morning and evening meals and an adequate amount of water. Do not consume grapefruit, grapefruit juice, or Seville oranges (also known as bitter or sour oranges).During treatment with lonafarnib. Juice from grapefruits and Seville oranges can increase the blood levels of lonafarnib. This may increase the risk and/or severity of side effects such as nausea, vomiting, diarrhea, loss of appetite, electrolyte (e.G., calcium, magnesium, potassium, phosphate, sodium) abnormalities, liver problems, low red and white blood cell counts, infection, and high blood pressure. 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.

Do not take iron supplements, multivitamins, calcium supplements, antacids, or laxatives within 2 hours before or after taking oxytetracycline. These products can make oxytetracycline less effective in treating your infection. Do not take oxytetracycline with milk or other dairy products, unless your doctor has told you to. Dairy products can make it harder for your body to absorb the medication.

Iron can bind to oxytetracycline in the gastrointestinal tract, which may prevent their absorption into the bloodstream and possibly reduce their effectiveness. To avoid or minimize the interaction, iron-containing medications and oxytetracycline should preferably be taken at least three to four hours apart in most cases. Talk to your doctor if you have any questions or concerns, or if you have trouble separating the dosing times. Your doctor may be able to prescribe alternatives that do not interact. 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.