Black Seed

Best for

Ease indigestion and heartburn

Large effect, needs confirmation · 1 meta-analysis , n=70

38 papers · 2 claims · 113 outcomes scored · 2 positive

Outcomes

What black seed actually does, by outcome

Each row is one outcome with effect size, evidence base, the dose that worked in trials, and time to first effect. Magnitude tiers come from native-unit MCID where available, Cohen's d otherwise.

Outcome Effect size Evidence Dose Weeks Rank

Ease indigestion and heartburn Large effect, needs confirmation

Less upper-stomach heaviness, burning, and acid discomfort after eating.

1 meta-analysis n=70 — — #6/11

37323050

large

1 meta-analysis n=70 Meta-analyzed

—

#6 /11

Improve overall digestive comfort Faint early signal

Less cramping, rumbling, and unease throughout your gut.

1 RCT n=55 3000 mg 2 wk #6/9

35631072

small

1 RCT n=55

3000 mg

2 wk

#6 /9

Forms & standardisation

The digestion studies here used plain oral black seed preparations, not a fancy branded extract.²³ On a label, look for Nigella sativa seed, black seed oil, or the actual milligram amount, because those are the forms with human data. If a product leans hard on thymoquinone standardization, that tells you about chemistry, but the digestive evidence still comes from very small trials.¹²³

Risk profile

Adverse events and known drug interactions

Safety events

renal_failure_acute severe

hypoxia and pneumonia (hospitalization, SAE) severe

nausea moderate

itching moderate

DRESS syndrome moderate

Maculopapular exanthema (generalized infiltrative rash) moderate

Eosinophilia moderate

gastrointestinal irritation mild

Drug interactions

Cyclosporine major increases concentration

Tacrolimus major increases concentration

Carbamazepine major increases concentration

Losartan major increases concentration

Dasatinib major increases concentration

Amoxicillin moderate increases concentration

Haloperidol moderate decreases concentration

Cisplatin moderate decreases concentration

Methotrexate moderate decreases concentration

Doxorubicin moderate decreases concentration

Co-studied with

Supplements that share evidence with black seed

Wheatbran 8 shared outcomes · d=0.12

Piperine 7 shared outcomes · d=0.81

Drug:Omeprazole 3 shared outcomes · d=0.52

Frequently asked

Common questions

What is black seed actually good for?

Right now, the most interesting human signal sits in digestion. Early studies show a real but unconfirmed effect for indigestion and a faint signal for overall digestive comfort.²³

Is black seed oil the same as black seed powder?

No, they are different forms. The human data here are too sparse to crown one winner, so the smart move is to match the form and dose used in the study you are copying.²³

How long does black seed take to work?

The studies ran for about 1.4 to 2 weeks, so any effect shows up quickly if it shows up at all.²³

Can you take black seed every day?

The available trials used daily dosing, not one-off use. That said, the safety picture is not boring, so daily use only makes sense if you tolerate it and your medication list is clean.²³

Track black seed in the app

Log doses, check interactions, compare it to alternatives — all backed by the same evidence base.

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Sources

Generated May 15, 2026