Drug Interaction Report
11 potential interactions and/or warnings found for the following 2 drugs:
- belladonna / ergotamine / phenobarbital
- deutivacaftor / tezacaftor / vanzacaftor
Interactions between your drugs
PHENobarbital tezacaftor
Applies to: belladonna / ergotamine / phenobarbital, deutivacaftor / tezacaftor / vanzacaftor
Consumer information for this interaction is not currently available.
GENERALLY AVOID: Coadministration with potent or moderate inducers of CYP450 3A4 may significantly decrease the plasma concentrations of vanzacaftor, tezacaftor, and deutivacaftor, drugs primarily metabolized by the isoenzyme. Physiologically based pharmacokinetic (PBPK) simulations suggest that coadministration with the potent CYP450 3A4 inducer rifampin may decrease vanzacaftor peak plasma concentration (Cmax) and systemic exposure (AUC) by 78% and 82%, respectively, and may decrease deutivacaftor Cmax and AUC by 80% and 90%, respectively. Similarly, the moderate CYP450 3A4 inducer efavirenz is predicted to decrease vanzacaftor Cmax and AUC by 65% and 69%, respectively; and may decrease deutivacaftor Cmax and AUC by 56% and 73%, respectively. No pharmacokinetic data are available for tezacaftor, but decreased exposures are expected according to prescribing information.
MANAGEMENT: Concomitant use of vanzacaftor, tezacaftor, and deutivacaftor containing medications with potent CYP450 3A4 inducers is not recommended.
PHENobarbital vanzacaftor
Applies to: belladonna / ergotamine / phenobarbital, deutivacaftor / tezacaftor / vanzacaftor
Consumer information for this interaction is not currently available.
GENERALLY AVOID: Coadministration with potent or moderate inducers of CYP450 3A4 may significantly decrease the plasma concentrations of vanzacaftor, tezacaftor, and deutivacaftor, drugs primarily metabolized by the isoenzyme. Physiologically based pharmacokinetic (PBPK) simulations suggest that coadministration with the potent CYP450 3A4 inducer rifampin may decrease vanzacaftor peak plasma concentration (Cmax) and systemic exposure (AUC) by 78% and 82%, respectively, and may decrease deutivacaftor Cmax and AUC by 80% and 90%, respectively. Similarly, the moderate CYP450 3A4 inducer efavirenz is predicted to decrease vanzacaftor Cmax and AUC by 65% and 69%, respectively; and may decrease deutivacaftor Cmax and AUC by 56% and 73%, respectively. No pharmacokinetic data are available for tezacaftor, but decreased exposures are expected according to prescribing information.
MANAGEMENT: Concomitant use of vanzacaftor, tezacaftor, and deutivacaftor containing medications with potent CYP450 3A4 inducers is not recommended.
PHENobarbital deutivacaftor
Applies to: belladonna / ergotamine / phenobarbital, deutivacaftor / tezacaftor / vanzacaftor
Consumer information for this interaction is not currently available.
GENERALLY AVOID: Coadministration with potent or moderate inducers of CYP450 3A4 may significantly decrease the plasma concentrations of vanzacaftor, tezacaftor, and deutivacaftor, drugs primarily metabolized by the isoenzyme. Physiologically based pharmacokinetic (PBPK) simulations suggest that coadministration with the potent CYP450 3A4 inducer rifampin may decrease vanzacaftor peak plasma concentration (Cmax) and systemic exposure (AUC) by 78% and 82%, respectively, and may decrease deutivacaftor Cmax and AUC by 80% and 90%, respectively. Similarly, the moderate CYP450 3A4 inducer efavirenz is predicted to decrease vanzacaftor Cmax and AUC by 65% and 69%, respectively; and may decrease deutivacaftor Cmax and AUC by 56% and 73%, respectively. No pharmacokinetic data are available for tezacaftor, but decreased exposures are expected according to prescribing information.
MANAGEMENT: Concomitant use of vanzacaftor, tezacaftor, and deutivacaftor containing medications with potent CYP450 3A4 inducers is not recommended.
ergotamine PHENobarbital
Applies to: belladonna / ergotamine / phenobarbital, belladonna / ergotamine / phenobarbital
PHENobarbital may reduce the blood levels and effects of ergotamine. Contact your doctor if your symptoms worsen or your condition changes during treatment with these medications. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both medications. 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.
Drug and food interactions
PHENobarbital food
Applies to: belladonna / ergotamine / phenobarbital
Ask your doctor before using PHENobarbital together with ethanol (alcohol), this can add to dizziness, drowsiness and other side effects of PHENobarbital. Be careful if you drive or do activities that require you to be awake and alert. Talk with your doctor before using any medications together, or drinking alcohol with PHENobarbital. 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.
ergotamine food
Applies to: belladonna / ergotamine / phenobarbital
Grapefruit juice may increase the blood levels of certain medications such as ergotamine. You may want to limit your consumption of grapefruit and grapefruit juice during treatment with ergotamine. However, if you have been regularly consuming grapefruit or grapefruit juice with the medication, then it is advisable for you to talk with your doctor before changing the amounts of these products in your diet, as this may alter the effects of your medication. Contact your doctor if your condition changes or you experience increased side effects. Orange juice is not expected to interact.
tezacaftor food
Applies to: deutivacaftor / tezacaftor / vanzacaftor
Consumer information for this interaction is not currently available.
GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of tezacaftor, deutivacaftor, and vanzacaftor. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation- dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. The risk and/or severity of serious side effects such as liver damage may be increased.
ADJUST DOSING INTERVAL: Administration with fat-containing food may increase the oral bioavailability of vanzacaftor and deutivacaftor. Administration with a fat containing meal increased vanzacaftor systemic exposure (AUC) by 4- (low-fat meal) to 6- (high-fat meal) fold. While deutivacaftor AUC increased approximately 3- (low-fat meal) to 4- (high-fat meal) fold, relative to administration in a fasting state. Tezacaftor exposure is not significantly affected by administration of fat-containing foods.
MANAGEMENT: Patients treated with tezacaftor, deutivacaftor, vanzacaftor -containing medications should avoid consumption of grapefruit juice and any food that contains grapefruit. To improve absorption, patients should be advised to take vanzacaftor and/or deutivacaftor containing medications with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products at approximately the same time of the day. A typical cystic fibrosis diet will satisfy this requirement.
vanzacaftor food
Applies to: deutivacaftor / tezacaftor / vanzacaftor
Consumer information for this interaction is not currently available.
GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of tezacaftor, deutivacaftor, and vanzacaftor. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation- dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. The risk and/or severity of serious side effects such as liver damage may be increased.
ADJUST DOSING INTERVAL: Administration with fat-containing food may increase the oral bioavailability of vanzacaftor and deutivacaftor. Administration with a fat containing meal increased vanzacaftor systemic exposure (AUC) by 4- (low-fat meal) to 6- (high-fat meal) fold. While deutivacaftor AUC increased approximately 3- (low-fat meal) to 4- (high-fat meal) fold, relative to administration in a fasting state. Tezacaftor exposure is not significantly affected by administration of fat-containing foods.
MANAGEMENT: Patients treated with tezacaftor, deutivacaftor, vanzacaftor -containing medications should avoid consumption of grapefruit juice and any food that contains grapefruit. To improve absorption, patients should be advised to take vanzacaftor and/or deutivacaftor containing medications with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products at approximately the same time of the day. A typical cystic fibrosis diet will satisfy this requirement.
deutivacaftor food
Applies to: deutivacaftor / tezacaftor / vanzacaftor
Consumer information for this interaction is not currently available.
GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of tezacaftor, deutivacaftor, and vanzacaftor. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation- dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. The risk and/or severity of serious side effects such as liver damage may be increased.
ADJUST DOSING INTERVAL: Administration with fat-containing food may increase the oral bioavailability of vanzacaftor and deutivacaftor. Administration with a fat containing meal increased vanzacaftor systemic exposure (AUC) by 4- (low-fat meal) to 6- (high-fat meal) fold. While deutivacaftor AUC increased approximately 3- (low-fat meal) to 4- (high-fat meal) fold, relative to administration in a fasting state. Tezacaftor exposure is not significantly affected by administration of fat-containing foods.
MANAGEMENT: Patients treated with tezacaftor, deutivacaftor, vanzacaftor -containing medications should avoid consumption of grapefruit juice and any food that contains grapefruit. To improve absorption, patients should be advised to take vanzacaftor and/or deutivacaftor containing medications with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products at approximately the same time of the day. A typical cystic fibrosis diet will satisfy this requirement.
belladonna food
Applies to: belladonna / ergotamine / phenobarbital
Ask your doctor before using belladonna together with ethanol (alcohol). Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking belladonna. You should be warned not to exceed recommended dosages and to avoid activities requiring mental alertness. If your doctor prescribes these medications together, you may need a dose adjustment to safely take this combination. 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.
ergotamine food
Applies to: belladonna / ergotamine / phenobarbital
Nicotine may increase the effects of ergotamine in narrowing the blood vessels and decreasing blood flow. A severe decrease in blood flow to the brain and other parts of the body can lead to dangerous side effects. Contact your doctor immediately if you experience coldness, paleness, discoloration, numbness, tingling, or pain in your hands or feet; muscle pain or weakness; severe or worsening headache; blurred vision; severe abdominal pain; chest pain; or shortness of breath while using these medications. 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.
Therapeutic duplication warnings
No duplication warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
Drug Interaction Classification
| Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
| Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
| Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
| No interaction information available. |
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