Thank you for your query at DoctorSpring.com
Well as of grapefruit it can be taken at breakfast.
For the other 2 medicines, ideally Levothyroxine should be taken empty stomach in the morning. That balances the thyroid levels for the rest of the day. What is the dose that has been recommended for you?
Regarding Diltiazem Hcl XC again it depends on the dose that has been prescribed and the blood pressure levels recently?
Both the medicines are safe provided there are proper indications, and the recommended dosage has not been exceeded.
Patient replied :
But is it safe to eat grapefruit or grapefruit juice with these medications, I read it was dangerous to eat or drink grapefruit with certain meds.
Yes you're right.Grpaefruit works by inhibiting CYP3A4 enzyme isoform in the blood, thereby limiting absorption of certain drugs such as Diazepam, Xanax, Alprazolam, Zoloft, Sertraline, e.t.c
It also retards the absorption of Levothyroxine, however that's why I advised you to take it empty stomach in the morning, because by the time you have breakfast and grapefruit juice, it would already be absorbed.
However I will advise you to avoid graefruit if possible because it is unique in the way of its mechanism of action of inhibiting an enzyme that helps in absorption of a lot of drugs in our body.
Feel free to discuss further,