There are multiple interactions reported between these two agents.

Interaction Details

Fosphenytoin is classified as belonging to the following category: Cns Depressants

Theoretically, concomitant use with drugs that have sedative properties may cause additive effects.
Animal research suggests that black seed may have CNS depressant effects.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • Al Naggar, T. B., Gomez-Serranillos, M. P., Carretero, M. E., and Villar, A. M. Neuropharmacological activity of Nigella sativa L. extracts. J Ethnopharmacol. 2003;88(1):63-68.

Interaction Details

Fosphenytoin is classified as belonging to the following category: Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, black seed might increase levels of drugs metabolized by CYP2C9.
In vitro research suggests that thymoquinone, a constituent of black seed, can decrease the metabolism of phenytoin by a mechanism possibly related to the inhibition of CYP2C9. The effect of black seed on CYP2C9 is unclear. This has not been shown in humans.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • Wang Z, Wang X, Wang Z, et al. Potential herb-drug interaction risk of thymoquinone and phenytoin. Chem Biol Interact. 2022;353:109801.

Interaction Details

Fosphenytoin is classified as belonging to the following category: Phenytoin (Dilantin)

Theoretically, black seed might increase levels and adverse effects of phenytoin.
In vitro research suggests that thymoquinone, a constituent of black seed, can decrease the metabolism of phenytoin. This effect may be due to inhibition of cytochrome P450 2C9 (CYP2C9). The effect of black seed on phenytoin metabolism is unclear. This has not been shown in humans.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • Wang Z, Wang X, Wang Z, et al. Potential herb-drug interaction risk of thymoquinone and phenytoin. Chem Biol Interact. 2022;353:109801.

Black Seed Overview

Black Seed Black seed, also known as black cumin, is a flowering plant belonging to the Ranunculaceae family. It is used in traditional medicine for the treatment of several conditions, including bronchitis, colic, fatigue, fever, headache, toothache, back pain, and infections. Most dietary supplements containing black seed market it as supporting the respiratory and digestive system, as well as improving immune health. Black seed oil is obtained from the seeds being cold-pressed. In regard to supplements, whole black seeds contain both the oil and other components such as fiber and proteins, while black seed oil is a concentrated source of the oil only. Both can be taken as supplements, but black seed oil contains larger amounts of active components, while whole seeds can provide additional nutrients and fiber.
See More Information Regarding Black Seed

Fosphenytoin Overview

  • Fosphenytoin injection is used to treat primary generalized tonic-clonic seizures (formerly known as a grand mal seizure; seizure that involves the entire body) and to treat and prevent seizures that may begin during or after surgery to the brain or nervous system. Fosphenytoin injection may also be used to control certain type of seizures in people who cannot take oral phenytoin. Fosphenytoin is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in the brain.

See More Information Regarding Fosphenytoin Injection

Black Seed - More Interactions

Black Seed interacts with 890 drugs

Interaction Rating Key

These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.

Major The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur.
Moderate Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur.
Minor Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction.
Unknown No interactions have been reported or no interaction data is currently available.

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Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Drug descriptions are provided by MedlinePlus.

Ask A Pharmacist About Your Herbal Questions!

Dr. Brian Staiger, PharmD

In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!

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