Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Senna Ingredients & Drug Interactions

by NOW

Senna label
See full label image
Other (e.g. Tea Bag) Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Senna against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Senna is a dietary supplement by NOW with 1 active ingredient. Its ingredients are commonly taken for short-term constipation relief, bowel cleansing before procedures, occasional irregularity.Based on those ingredients, 140 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are organic Senna. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Senna by NOW

Ask about any prescription or over-the-counter medication and we check it for interactions with Senna by NOW — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Senna by NOW

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

NOW Senna contains one active ingredient: organic senna leaf. Senna is a stimulant laxative—it works by triggering muscle contractions in your colon to move stool forward.

There are no other active ingredients in this product.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Relief for occasional constipation.
  • We looked for evidence on: Constipation, Bowel preparation, Occasional irregularity, Digestive regularity.
  • The strongest evidence on file: Senna is rated "Likely Effective" for Constipation (Natural Medicines).
  • Also on file: Senna is rated "Possibly Effective" for Bowel preparation.

Senna is likely effective for constipation. It's possibly effective for bowel preparation (the cleansing before a medical procedure).

The evidence for using senna to treat high potassium levels (hyperkalemia) is insufficient to rate.

The evidence, ingredient by ingredient Senna

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Senna is generally well tolerated when you use it short-term in standard doses. The most common side effects are abdominal cramping, pain and discomfort, diarrhea, nausea, gas, and urgent bowel movements; some people also notice their urine changes color.

Serious side effects are rare but have included skin reactions (rash, blistering, and in very rare cases toxic epidermal necrolysis, a severe blistering condition). Excessive long-term use has been linked to rare reports of finger clubbing, bone overgrowth, muscle weakness (tetany), and wasting.

Do not use senna long-term without your doctor's guidance. The safety data we hold does not include pregnancy or breastfeeding information for this ingredient—talk with your pharmacist or doctor before using it if you're pregnant or nursing.

Side effects, ingredient by ingredient Senna

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Senna.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; heart-rhythm medications.
  • For scale: 140 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you start NOW Senna, check your medications against these types: blood thinners like warfarin (Coumadin), heart medications including digoxin (Lanoxin), diuretics (water pills), other stimulant laxatives, and estrogen-based hormonal contraceptives or hormone therapy. All carry moderate-severity interactions with senna.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Senna is an effective short-term remedy for constipation, best used occasionally and under medical advice rather than daily. If you take a blood thinner like warfarin, a heart medication like digoxin, a water pill, or hormonal contraceptives, you need to check with your pharmacist before using this product.

Even at standard doses, talk to your doctor first—senna isn't meant for long-term daily use.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Sep 21, 2017.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Senna, straight from the product label.

Brand NOW
Barcode (UPC) 733739042361
Net contents 24 Tea Bag(s); 1.7 oz.; 48 Gram(s)
Market status On market
Date entered into DSLD Sep 21, 2017
DSLD ID 78032
Product type Botanical
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Kosher, Organic, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Senna by NOW, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Tea Bag(s)
Maximum serving Sizes:
1 Tea Bag(s)
Servings per container
24
UPC/BARCODE
733739042361
IngredientAmount% DV
Calories0 Calorie(s)--
organic Senna2 Gram(s)--

Other ingredients: None

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Premium unbleached tea bags with our no-staples design.

We source only the highest quality ingredients so you can enjoy the most delicious, healthful tea every day. If you don't love this tea as much as we do, we'll happily refund your money.

Because you are what you eat and drink, NOW Real Food and Real Tea have been committed to providing delicious, healthy, natural products since 1968. We’re independent, family owned, and proud of it. Keep it natural. Keep it real.

Relief for occasional constipation

Real Tea

A traditional herbal bowel stimulant to help relieve occasional constipation

Sometimes you just gotta go. And Organic Senna herbal tea can get you going. A trusted laxative, it also supports bowel health and can help the body detoxify. It’s your belly’s best buddy.

Brew it natural. Sip it real.

Formulation

Contains no artificial colors, flavors, preservatives, or sugars.

Non-GMO

Caffeine-free

Certified Organic by QAI

Seals/Symbols

USDA Organic

Non GMO Project Verified nongmoproject.org

Triangle K

Formula

Triangle K

Notice: This product contains senna.

FDA Statement of Identity

A Dietary Supplement

Suggested/Recommended/Usage/Directions

Instructions: Steep one tea bag in 6-8 ounces of boiling water for 4-6 minutes. Stir occasionally while steeping. Do not consume more than two cups per day. For occasional use only; do not use daily for longer than 1 to 2 weeks.

Precautions

Do not give to children.

Notice: This product contains senna. Read and follow directions carefully. Do not use if you have or develop diarrhea, loose stools, or abdominal pain because senna may worsen these conditions and be harmful to your health.

Consult your physician if you have frequent diarrhea or if you are pregnant, nursing, taking medication, or have a medical condition.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

General

CODE 4236B V8

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Senna by NOW label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Senna label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Senna by NOW

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Tea Bag(s) Dosage formOther (e.g. Tea Bag) Servings per container24 Amounts shown are per serving.

Organic Senna

Interacts with
140 drugs
2 Gram(s) per serving

Senna is a plant-based stimulant laxative that is widely used and generally effective for short-term relief of constipation. It is best used occasiona...

Organic Senna monograph & interactions

Other (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.

Interaction report

Senna by NOW Drug Interactions

Want to check YOUR meds against Senna?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
140Drugs
140 Moderate

Ingredients driving the most interactions

organic Senna 140

Individual Drug Interactions

The ingredients in Senna interact with 140 drugs. Click any drug to see the details.

1 of the 1 ingredient in Senna interact with drugs. Each result below shows which ingredient is responsible. organic Senna

Each ingredient & the kinds of drugs it affects

For each ingredient in Senna with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

organic Senna5 drug types · 140 drugs

Digoxin (Lanoxin)

Theoretically, senna might increase the risk of adverse effects when taken with digoxin.
Overuse/abuse of senna increases the risk of adverse effects from cardiac glycosides, such as digoxin, due to potassium depletion.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, senna might increase the risk of hypokalemia when taken with diuretic drugs.
Overuse of senna might compound diuretic-induced potassium loss and increase the risk for hypokalemia.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking senna may interfere with the absorption of exogenous estrogens.
Some preliminary clinical evidence suggests that senna reduces the absorption of estradiol and decreases serum concentrations of estrone and estrone sulfate by decreasing intestinal transit time.

Likelihood Possible Evidence B
Stimulant Laxatives

Theoretically, senna might increase the risk for fluid and electrolyte loss when taken with other stimulant laxatives.
Senna is a stimulant laxative; concomitant use with other stimulant laxatives might compound fluid and electrolyte loss.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, excessive use of senna might increase the effects of warfarin.
Senna has stimulant laxative effects and can cause diarrhea. Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding. In one case report, excessive use of senna for 3 weeks resulted in diarrhea, bloody stools, and an elevated INR of 11.9.

Likelihood Possible Evidence D
organic Senna full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Senna, from the product label.

NOW

See all NOW products
Name
NOW FOODS
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
www.nowfoods.com
Pharmacist Counseling Corner

Senna by NOW: Common Questions

Does Senna by NOW interact with any medications?
Yes. Based on its ingredients, Senna has a known interaction with 140 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Senna contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is senna safe to take every day?
Not without medical advice. Senna is generally well tolerated short-term in standard doses, but it's not recommended for long-term daily use without your doctor's guidance. Overuse can deplete potassium, cause excessive fluid loss, and rarely trigger serious complications.
What's the most common side effect?
Abdominal cramping and diarrhea are the most common side effects. You might also notice gas, nausea, urgent bowel movements, and a change in urine color. These are usually mild and expected when you use a stimulant laxative.
Can I use senna if I take a water pill?
Not without checking with your pharmacist first. Senna and diuretics together can cause dangerously low potassium levels (hypokalemia). Your pharmacist can assess your specific situation and tell you whether it's safe.
Does senna affect birth control?
Possibly. Senna may interfere with how your body absorbs estrogen-based contraceptives, which could reduce their effectiveness. Talk with your pharmacist or doctor before using senna if you take hormonal birth control.
How quickly does senna work?
The product facts we hold don't specify how long senna takes to work. Ask your pharmacist what to expect based on the form and dose you're using.
Can I use senna if I'm pregnant?
There isn't enough data on file to know whether senna is safe in pregnancy. Talk with your pharmacist or doctor for personalized advice before using it.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Senna is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Senna label
Go deeper

The Full Monographs Behind Senna’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Senna

Interacts with 140 drugs

Senna is a plant-based stimulant laxative that is widely used and generally effective for short-term relief of constipation. It is best used occasionally and for only a few days at a time, s...

Read the full Senna monograph →
Sources

Sources & How We Checked

Senna's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 42 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Senna 42 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. American Academy of Pediatrics. The transfer of drugs and other chemicals into human milk. Pediatrics 2001;108:776-89. PubMed
  4. Nusko G, Schneider B, Schneider I, et al. Anthranoid laxative use is not a risk factor for colorectal neoplasia: results of a prospective case control study. Gut 2000;46:651-5. PubMed
  5. Seybold U, Landauer N, Hillebrand S, Goebel FD. Senna-induced hepatitis in a poor metabolizer. Ann Intern Med 2004;141:650-1. PubMed
  6. Vanderperren B, Rizzo M, Angenot L, et al. Acute liver failure with renal impairment related to the abuse of senna anthraquinone glycosides. Ann Pharmacother 2005;39:1353-7. PubMed
  7. Xing JH, Soffer EE. Adverse effects of laxatives. Dis Colon Rectum 2001;44:1201-9. PubMed
  8. Prior J, White I. Tetany and clubbing in patient who ingested large quantities of senna. Lancet 1978;2:947. PubMed
  9. Langmead L, Rampton DS. Review article: herbal treatment in gastrointestinal and liver disease--benefits and dangers. Aliment Pharmacol Ther 2001;15:1239-52. PubMed
  10. Joo JS, Ehrenpreis ED, Gonzalez L, et al. Alterations in colonic anatomy induced by chronic stimulant laxatives: the cathartic colon revisited. J Clin Gastroenterol 1998;26:283-6. PubMed
  11. Godding EW. Laxatives and the special role of senna. Pharmacology 1988;36:230-6. PubMed
  12. van Os FH. Anthraquinone derivatives in vegetable laxatives. Pharmacology 1976;14:7-17. PubMed
  13. Sondheimer JM, Gervaise EP. Lubricant versus laxative in the treatment of chronic functional constipation of children: a comparative study. J Pediatr Gastroenterol Nutr 1982;1:223-6. DOI
  14. Perkin JM. Constipation in childhood: a controlled comparison between lactulose and standardized senna. Curr Med Res Opin 1977;4:540-3. PubMed
  15. Shelton MG. Standardized senna in the management of constipation in the puerperium: A clinical trial. S Afr Med J 1980;57:78-80.
  16. [No authors listed] Senna in the puerperium. Pharmacology 1992;44:23-5. PubMed
  17. Passmore AP, Davies KW, Flanagan PG, et al. A comparison of Agiolax and lactulose in elderly patients with chronic constipation. Pharmacology 1993;47:249-52. PubMed
  18. Passmore AP, Wilson-Davies K, Stoker C, Scott ME. Chronic constipation in long stay elderly patients: a comparison of lactulose and a senna-fibre combination. BMJ 1993;307:769-71. PubMed
  19. MacLennan WJ, Pooler AFWM. A comparison of sodium picosulphate ("Laxoberal") with standardised senna ("Senokot") in geriatric patients. Curr Med Res Opin. 1974;2:641-7. PubMed
  20. Kittisupamongkol W, Nilaratanakul V, Kulwichit W. Near-fatal bleeding, senna, and the opposite of lettuce. Lancet 2008;371:784. PubMed
  21. Prather CM. Pregnancy-related constipation. Curr Gastroenterol Rep 2004;6:402-4. PubMed
  22. Werthmann WM Jr, Krees SV. Quantitative excretion of Senokot in human breast milk. Med Ann Dist Columbia 1973;42:4-5.
  23. Hagemann TM. Gastrointestinal medications and breastfeeding. J Hum Lact 1998;14:259-62. PubMed
  24. Faber P, Strenge-Hesse A. Senna-containing laxatives: excretion in the breast milk? Geburtshilfe Frauenheilkd 1989;49:958-62.
  25. Faber P, Strenge-Hesse A. Relevance of rhein excretion into breast milk. Pharmacology 1988;36 Suppl 1:212-20. PubMed
  26. Duncan AS. Standardized senna as a laxative in the puerperium; a clinical assessment. Br Med J 1957;1:439-41. PubMed
  27. Stickel, F. and Schuppan, D. Herbal medicine in the treatment of liver diseases. Dig.Liver Dis. 2007;39(4):293-304. PubMed
  28. BALDWIN, W. F. CLINICAL STUDY OF SENNA ADMINISTRATION TO NURSING MOTHERS: ASSESSMENT OF EFFECTS ON INFANT BOWEL HABITS. Can.Med Assoc.J 9-14-1963;89:566-568. DOI
  29. Sonmez, A., Yilmaz, M. I., Mas, R., Ozcan, A., Celasun, B., Dogru, T., Taslipinar, A., and Kocar, I. H. Subacute cholestatic hepatitis likely related to the use of senna for chronic constipation. Acta Gastroenterol.Belg. 2005;68(3):385-387.
  30. Beuers, U., Spengler, U., and Pape, G. R. Hepatitis after chronic abuse of senna. Lancet 2-9-1991;337(8737):372-373. PubMed
  31. Lim, A. K., Hooke, D. H., and Kerr, P. G. Anorexia nervosa and senna misuse: nephrocalcinosis, digital clubbing and hypertrophic osteoarthropathy. Med J Aust. 1-21-2008;188(2):121-122. PubMed
  32. McLaughlin, A. F. Anorexia nervosa and senna misuse: nephrocalcinosis, digital clubbing and hypertrophic osteoarthropathy. Med J Aust. 9-15-2008;189(6):348. PubMed
  33. Soyuncu, S., Cete, Y., and Nokay, A. E. Portal vein thrombosis related to Cassia angustifolia. Clin.Toxicol.(Phila) 2008;46(8):774-777.
  34. Levine, D., Goode, A. W., and Wingate, D. L. Purgative abuse associated with reversible cachexia, hypogammaglobulinaemia, and finger clubbing. Lancet 4-25-1981;1(8226):919-920. PubMed
  35. Malmquist, J., Ericsson, B., Hulten-Nosslin, M. B., Jeppsson, J. O., and Ljungberg, O. Finger clubbing and aspartylglucosamine excretion in a laxative-abusing patient. Postgrad.Med J 1980;56(662):862-864. PubMed
  36. Lewis, S. J., Heaton, K. W., Oakey, R. E., and McGarrigle, H. H. Lower serum oestrogen concentrations associated with faster intestinal transit. Br.J Cancer 1997;76(3):395-400. PubMed
  37. Lewis, S. J., Oakey, R. E., and Heaton, K. W. Intestinal absorption of oestrogen: the effect of altering transit-time. Eur.J Gastroenterol.Hepatol. 1998;10(1):33-39. PubMed
  38. Vilanova-Sanchez A, Gasior AC, Toocheck N, et al. Are Senna based laxatives safe when used as long term treatment for constipation in children? J Pediatr Surg 2018;53(4):722-7. PubMed
  39. Cogley K, Echevarria A, Correa C, De la Torre-Mondragón L. Contact Burn with Blister Formation in Children Treated with Sennosides. Pediatr Dermatol 2017;34(2):e85-e88. PubMed
  40. Coskun Y, Yuksel I. Polyethylene glycol versus split high-dose senna for bowel preparation: A comparative prospective randomized study. J Gastroenterol Hepatol 2020;35(11):1923-1929.
  41. Haoudar A, Chekhlabi N, El Kettani C, Dini N. Acute Hepatitis and Pancytopenia in a Child With Chronic Abuse of Senna. Cureus 2021;13(1):e12436. PubMed
  42. Irazábal B, Sánchez de Vicente J, Galán C, et al. Anaphylaxis Due to Senna (Cassia angustifolia). J Investig Allergol Clin Immunol 2021;31(1):71-73. PubMed

See these in context on the Senna monograph →

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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team