Broccoli, Broccoli Supplements, and Gabapentin: What You Need to Know

There is no evidence that eating broccoli or taking broccoli-based supplements directly interferes with gabapentin’s absorption or reduces its effectiveness. Gabapentin’s absorption is only slightly influenced by food in general, and the change is small and not clinically concerning. ^[1] Food causes about a 14% increase in overall exposure (AUC and peak level), which means gabapentin can typically be taken with or without meals. ^[2]

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How Gabapentin Is Absorbed

• Saturable transport: Gabapentin is absorbed in the small intestine via a saturable L‑amino acid transport system; increasing the dose beyond a certain point lowers the fraction absorbed. ^[3]
• Food effect is minimal: Standard meals have a small effect on gabapentin exposure (around 14% increase), and this is not considered harmful or clinically significant. ^{[1] [2]}

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Proven Interactions: Antacids and Minerals

While broccoli itself is not known to impair gabapentin absorption, certain antacid ingredients and minerals can.

• Magnesium-containing antacids (e.g., magnesium oxide, Maalox): Can reduce gabapentin absorption by roughly 20–40%, depending on timing and formulation. Taking gabapentin at least 2 hours after magnesium/aluminum antacids lessens this effect. ^{[4] [5]}
• Mechanism and timing: The reduction in exposure with magnesium oxide reflects decreased intestinal absorption rate and extent, not changes in kidney handling. ^[5]

Practical guidance

• Separate dosing: If you use magnesium/aluminum antacids, try to take gabapentin at least 2 hours apart to reduce the interaction. ^[4]

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Broccoli Compounds (Isothiocyanates) and Drug Metabolism: Why This Doesn’t Apply to Gabapentin

Broccoli contains isothiocyanates such as sulforaphane, which can influence drug-metabolizing enzymes (Phase I/II) and certain efflux transporters (e.g., ABC transporters). ^{[6] [7]} In theory, these dietary compounds might alter the pharmacokinetics of drugs that rely on liver enzymes or transporter systems.

• Gabapentin is different: Gabapentin is not metabolized by the liver, does not bind significantly to plasma proteins, and is eliminated unchanged by the kidneys. ^[1]
• Absorption pathway: Because gabapentin uses a specific amino acid transporter in the proximal small intestine and is not a classic substrate of CYP enzymes or P‑glycoprotein-like efflux pumps in clinical practice, the general enzyme/transporter effects of isothiocyanates are unlikely to materially impact gabapentin’s absorption or efficacy. ^[3]

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Food and Dosing Considerations

• With or without food: You can take gabapentin with meals or on an empty stomach; the slight increase in exposure with food is not typically clinically important. ^{[2] [1]}
• Dose-related bioavailability: As total daily dose rises (e.g., 900–4800 mg/day), the fraction absorbed decreases due to transporter saturation; this is inherent to gabapentin and unrelated to broccoli. ^[1]

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Key Takeaways

• Broccoli and standard broccoli supplements are not known to reduce gabapentin’s absorption or effectiveness. ^{[1] [2]}
• Magnesium/aluminum antacids can lower absorption separate them from gabapentin by at least 2 hours. ^{[4] [5]}
• Isothiocyanates from cruciferous vegetables can affect drug‑metabolizing enzymes and some transporters, but gabapentin’s unique absorption and renal elimination make meaningful interactions unlikely. ^{[6] [7] [3]}

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Quick Reference Table

Item	Effect on Gabapentin	Notes
Regular meals	Slight ↑ in exposure (~14%)	Not clinically significant; take with or without food. [2] [1]
Broccoli foods/supplements	No proven reduction in absorption	No clinical data showing impairment; theoretical enzyme/transporter effects do not apply meaningfully to gabapentin. [6] [7] [3]
Magnesium/aluminum antacids	↓ exposure by ~20–40%	Separate dosing by ≥2 hours to minimize impact. [4] [5]

If you’re using antacids or mineral supplements, adjusting timing is a simple way to keep gabapentin working as intended. ^{[4] [5]}