In one study, ingestion of 250 ml (approximately one cup) of grapefruit juice one hour before and together with
sildenafil increased the total amount of sildenafil absorbed by 23%, but tended to delay the
absorption of the drug.1 The authors of this study recommended that sildenafil and
grapefruit juice not be taken together.
Summary of
Interactions with Vitamins, Herbs, and Foods
In some cases, an herb or supplement may appear in more than one category, which may seem
contradictory. For clarification, read the full article for details about the summarized
interactions.
Avoid: Adverse interaction—Avoid these supplements when taking this
medication because taking them together may cause undesirable or dangerous results. |
Grapefruit juice
|
| Depletion or interference |
None known
|
| Side effect reduction/prevention |
None known
|
| Supportive interaction |
None known
|
| Reduced drug
absorption/bioavailability |
None known
|
An asterisk (*) next to an item in the summary indicates that the
interaction is supported only by weak, fragmentary, and/or contradictory scientific
evidence.
References:1. Jetter A, Kinzig-Schippers M, Walchner-Bonjean M, et al. Effects of
grapefruit juice on the pharmacokinetics of sildenafil. Clin Pharmacol Ther
2002;71:21–9.