I don't know specifically about vardenafil, but grapefruit has substances that interfere with liver enzymes involved in metabolizing many drugs. Combining grapefruit with these drugs can often lead to dangerous elevations of the drug levels.
No. Grapefruit interferes with the action of statin drugs that most Type 1 diabetics also take.
Is it safe to mix grapefruit and metoprolol
If you take amlodipine -- or any other kind of calcium channel blocker -- do not take them with grapefruit, grapefruit juice or grapefruit dietary supplements, because serious, possibly fatal, reactions may occur. Grapefruit inhibits your CYP34A enzyme, a protein that helps your body metabolize drugs. When your body fails to properly metabolize drugs, you may end up with more of amlodipine in your system than intended, causing an accidental overdose. Some drugs -- and some people -- react more strongly than others to the effect of grapefruit on your CYP34A enzyme.
This question is a bit hard to understand, but I'm aware that grapefruit has a number of interactions with other drugs. It affects diabetic drugs and many other common ones so it's worth checking for the interactions.
Studies up to now show that the juice and the fruit have both a significant interaction with some drugs (including lipitor).
I personally like grapefruit a little bit. They are a bit sour (and sweet) but taste pretty good.
The negative effects of drinking grapefruit juice include negative interactions with certain drugs, which increase blood levels of the drug to harmful levels. Grapefruit juice inhibits a chemical in the intestine needed to break down many drugs in the body, making the drug become more potent.
Cimetidine and/or grapefruit juice make benzo's (among many other drugs) have a stronger effect.
Grapefruit juice
The human body uses many methods to eliminate waste and foreign compounds (kidneys, liver, saliva, others). Grapefruit is eliminated by an enzyme pathway in the liver that is also a common pathway for many drugs. Grapefruit in combination with these drugs can overwhelm the livers ability to filter the compounds, leading in slower drug elimination and therefore higher than desired blood levels.Speak with your doctor or pharmacist to determine if any drugs you use interact with grapefruit.A bit more:You should not eat grapefruit or drink grapefruit juice while taking Diazepam (Valium).
Nothing will happen if you mix Zithromax with grapefruit. The only types of drugs that are affected by grapefruits are sedatives, antianxiety agents, calcium channel blockers, and statins.