Drug & supplement interaction

Guar Gum + Mepolizumab

Mepolizumab brand name: Nucala.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 13, 2026

The bottom line No known interaction

We found no known interaction between Guar Gum and Mepolizumab in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

Know someone taking this? Share

Facebook Post Reddit Email

On this page

Interaction report

Guar Gum and Mepolizumab

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Mepolizumab and Guar Gum in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Guar Gum safety at a glance

Guar Gum overall Use caution Generally safe as a food, but supplements must be taken with lots of water to avoid choking or blockage.

Pregnancy Possibly Safe When used orally and appropriately in medicinal amounts. Guar gum has been safely used at doses of 5-15 grams daily for up to 4 weeks during pregnancy. Read the full pregnancy detail

Breastfeeding Use caution Little safety data on supplement doses, so it is best to be cautious and ask your doctor.

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Mepolizumab and Guar Gum? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

Keep it in perspective

Guar Gum Does Interact With Other Medications

Guar Gum has 2,025 moderate known drug interactions in our database — Mepolizumab isn’t one of them. If you take anything else, check it against the full list below.

Moderate 2,025 No known interaction 805 (incl. Mepolizumab)

Taking anything else?

Check Another of Your Medications Against Guar Gum

Covers the 2,830 medications we’ve checked against Guar Gum. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Guar Gum and Mepolizumab May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

Wheezing Worth acting on reported in 40.3% of FDA reports for Mepolizumab Additional detail
Guar Gum
“Occupational exposure to guar gum may cause asthma.”

Guar Gum · Natural Medicines adverse-effect record, reported in asthma.
2 sources cited

600. Malo JL, Cartier A, L'Archeveque J, et al. Prevalence of occupational asthma and immunologic sensitization to guar gum among employees at a carpet-manufacturing plant. J Allergy Clin Immunol 1990;86:562-9. PubMed

601. Lagier F, Cartier A, Somer J, et al. Occupational asthma caused by guar gum. J Allergy Clin Immunol 1990;85:785-90.
Mepolizumab

Listed in the ADVERSE REACTIONS section of the FDA label for Mepolizumab, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›
Stomach pain / Diarrhea Additional detail
Guar Gum
“Orally, guar gum may cause gastrointestinal adverse effects such as abdominal cramps, abdominal pain, bloating, diarrhea, flatulence, heartburn, gas, and loose stools. Gastrointestinal side effects can be minimized by starting with small doses and titrating up.”

Guar Gum · Natural Medicines adverse-effect record, reported in diarrhea.
6 sources cited

10896. Vuorinen-Markkola H, Sinisalo M, Koivisto VA. Guar gum in insulin-dependent diabetes: effects on glycemic control and serum lipoproteins. Am J Clin Nutr 1992;56:1056-1060. PubMed

10897. Superko HR, Haskell WL, Sawrey-Kubicek L, Farquhar JW. Effects of solid and liquid guar gum on plasma cholesterol and triglyceride concentrations in moderate hypercholesterolemia. Am J Cardiol 1988;62:51-5. PubMed

12541. Groop PH, Aro A, Stenman S, Groop L. Long-term effects of guar gum in subjects with non-insulin-dependent diabetes mellitus. Am J Clin Nutr 1993;58:513-8. PubMed

12543. Chuang LM, Jou TS, Yang WS, et al. Therapeutic effect of guar gum in patients with non-insulin-dependent diabetes mellitus. J Formos Med Assoc 1992;91:15-9.

12545. Ebeling P, Yki-Jarvinen H, Aro A, et al. Glucose and lipid metabolism and insulin sensitivity in type 1 diabetes: the effect of guar gum. Am J Clin Nutr 1988;48:98-103. PubMed

12547. Knopp RH, Superko HR, Davidson M, et al. Long-term blood cholesterol-lowering effects of a dietary fiber supplement. Am J Prev Med 1999;17:18-23. PubMed
Mepolizumab

Listed in the ADVERSE REACTIONS section of the FDA label for Mepolizumab. Read the label on DailyMed ›

Reported for Guar Gum but not commonly for Mepolizumab: a bowel blockage, bloating or gas and heartburn.

Effects for Mepolizumab come from the ADVERSE REACTIONS section of its FDA label; effects for Guar Gum come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 49,399 voluntary FDA FAERS reports for Mepolizumab that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Guar Gum in Pregnancy & Breastfeeding

Pregnancy Possibly Safe

When used orally and appropriately in medicinal amounts. Guar gum has been safely used at doses of 5-15 grams daily for up to 4 weeks during pregnancy.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

One more smart check

Taking Guar Gum as Part of a Dietary Supplement Product? Check It for Interactions

We hold 33 real supplement products containing Guar Gum, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Guar Gum. Even though Guar Gum itself has no known interaction with Mepolizumab, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Guar Gum and Mepolizumab Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Guar Gum

Top half

#496 of 1,452 supplements looked up here in the last 7 days

29 days ago today

Medication Mepolizumab

Steady interest

#1,633 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?

Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Guar Gum reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Guar Gum and Mepolizumab records this page draws on were last updated July 11, 2026.
What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.

Data structure & sourcing designed and verified by Dr. Brian Staiger, PharmD, BCPS.

Supplement

About Guar Gum

What is Guar Gum?

Constipation and bowel regularity
Diarrhea (as a stool bulking agent)
Lowering cholesterol
Blood sugar control
Feeling full for weight management

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generally safe in food amounts, but concentrated supplements can cause gas, bloating, and a risk of throat or gut blockage if not taken with enough water. Always take it with plenty of fluid and check with your pharmacist or doctor first.

Cyamopsis tetragonoloba · Fabaceae · Seeds (endosperm) · Powder, capsules, tablets, partially hydrolyzed guar gum (in some fiber drinks); also a food additive

An interaction check asks whether these two react with each other — it does not ask whether Guar Gum is a good idea for someone in your situation. Here is what our Guar Gum record says about it on its own.

Guar Gum: dosing

There is no single official dose for guar gum as a supplement. The right amount depends on the product and why you are taking it.The best approach is to follow the directions on the product label and start with a low amount.

From our Guar Gum monograph — the full record covers uses, side effects and every documented interaction.

Read the full Guar Gum monograph & all interactions

Medication

About Mepolizumab Injection

What Is Mepolizumab Injection Used For?

Brand name: Nucala

Nucala is used as an add-on maintenance treatment — meaning it works alongside other medications, not instead of them. It is approved for severe asthma (in patients 6 years and older with high eosinophil levels), chronic rhinosinusitis with nasal polyps (CRSwNP) in adults 18 and older whose symptoms aren't controlled by nasal corticosteroids alone, and COPD in adults with an eosinophilic phenotype whose disease isn't adequately controlled.

Nucala is also approved to treat eosinophilic granulomatosis with polyangiitis (EGPA), a rare form of blood vessel inflammation, and hypereosinophilic syndrome (HES), a condition involving dangerously elevated eosinophil counts, in adults and adolescents 12 and older. It is not meant to relieve sudden asthma attacks or acute COPD flares.

Most-Reported Side Effects for Mepolizumab

From FAERS, the FDA’s public side-effect reporting system (49,399 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Asthma 12,767 reports

Dyspnea 10,576 reports

Wheezing 7,131 reports

Cough 5,100 reports

Therapeutic product effect incomplete 5,051 reports

See full Mepolizumab Injection drug information

Keep checking

Other Drugs & Guar Gum

Browse every other medication we’ve checked against Guar Gum — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major

2,025Moderate

0Minor

804No known interaction

2,025 Moderate 804 No interaction

Moderate

2,025 interactions

Showing 60 of 2,025 moderate interactions — see all 2,025 on the Guar Gum page.

No interaction 804 drugs checked — show the list

We also checked Guar Gum against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 804 medications checked with no known interaction — see the full Guar Gum list.

See the full Guar Gum interactions page

See every supplement checked against Mepolizumab, ranked by severity

Evidence & sources

Guar Gum References

The 26 references that drive our Guar Gum monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

Gin H, Orgerie MB, Aubertin J. The influence of Guar gum on absorption of metformin from the gut in healthy volunteers. Horm Metab Res 1989;21:81-3.
Huupponen R, Seppala P, Iisalo E. Effect of guar gum, a fibre preparation, on digoxin and penicillin absorption in man. Eur J Clin Pharmacol 1984;26:279-81. PubMed
Malo JL, Cartier A, L'Archeveque J, et al. Prevalence of occupational asthma and immunologic sensitization to guar gum among employees at a carpet-manufacturing plant. J Allergy Clin Immunol 1990;86:562-9. PubMed
Lagier F, Cartier A, Somer J, et al. Occupational asthma caused by guar gum. J Allergy Clin Immunol 1990;85:785-90.
Lewis JH. Esophageal and small bowel obstruction from guar gum-containing diet pills: analysis of 26 cases reported to the FDA. Am J Gastroenterol 1992;87:1424-8.
Vuorinen-Markkola H, Sinisalo M, Koivisto VA. Guar gum in insulin-dependent diabetes: effects on glycemic control and serum lipoproteins. Am J Clin Nutr 1992;56:1056-1060. PubMed
Superko HR, Haskell WL, Sawrey-Kubicek L, Farquhar JW. Effects of solid and liquid guar gum on plasma cholesterol and triglyceride concentrations in moderate hypercholesterolemia. Am J Cardiol 1988;62:51-5. PubMed
Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
Groop PH, Aro A, Stenman S, Groop L. Long-term effects of guar gum in subjects with non-insulin-dependent diabetes mellitus. Am J Clin Nutr 1993;58:513-8. PubMed
Chuang LM, Jou TS, Yang WS, et al. Therapeutic effect of guar gum in patients with non-insulin-dependent diabetes mellitus. J Formos Med Assoc 1992;91:15-9.
Ebeling P, Yki-Jarvinen H, Aro A, et al. Glucose and lipid metabolism and insulin sensitivity in type 1 diabetes: the effect of guar gum. Am J Clin Nutr 1988;48:98-103. PubMed
Scheen AJ. Clinical pharmacokinetics of metformin. Clin Pharmacokinet 1996;30:359-71. PubMed
Knopp RH, Superko HR, Davidson M, et al. Long-term blood cholesterol-lowering effects of a dietary fiber supplement. Am J Prev Med 1999;17:18-23. PubMed
Patrick PG, Gohman SM, Marx SC, et al. Effect of supplements of partially hydrolyzed guar gum on the occurrence of constipation and use of laxative agents. J Am Diet Assoc 1998;98:912-4. PubMed
Osterlund P, Ruotsalainen T, Korpela R, et al. Lactobacillus supplementation for diarrhoea related to chemotherapy of colorectal cancer: a randomised study. Br J Cancer 2007;97:1028-34. PubMed
Lembcke B, Hasler K, Kramer P, et al. Plasma digoxin concentrations during administration of dietary fibre (guar gum) in man. Z Gastroenterol 1982;20;164-7.
Riikonen, S., Savonius, H., Gylling, H., Nikkila, K., Tuomi, A. M., and Miettinen, T. A. Oral guar gum, a gel-forming dietary fiber relieves pruritus in intrahepatic cholestasis of pregnancy. Acta Obstet.Gynecol.Scand. 2000;79(4):260-264. DOI
Kovacs, E. M., Westerterp-Plantenga, M. S., Saris, W. H., Goossens, I., Geurten, P., and Brouns, F. The effect of addition of modified guar gum to a low-energy semisolid meal on appetite and body weight loss. Int.J.Obes.Relat Metab Disord. 2001;25(3):307 PubMed
Halama, W. H. and Mauldin, J. L. Distal esophageal obstruction due to a guar gum preparation (Cal-Ban 3000). South.Med.J. 1992;85(6):642-645. PubMed
Landin, K., Holm, G., Tengborn, L., and Smith, U. Guar gum improves insulin sensitivity, blood lipids, blood pressure, and fibrinolysis in healthy men. Am.J.Clin.Nutr. 1992;56(6):1061-1065. PubMed
Cicero, A. F., Derosa, G., Manca, M., Bove, M., Borghi, C., and Gaddi, A. V. Different effect of psyllium and guar dietary supplementation on blood pressure control in hypertensive overweight patients: a six-month, randomized clinical trial. Clin.Exp.Hyp PubMed
Simons LA, Gayst S, Balasubramaniam S, Ruys J. Long-term treatment of hypercholesterolaemia with a new palatable formulation of guar gum. Atherosclerosis 1982;45:101-108. PubMed
Salenius JP, Harju E, Jokela H, et al. Long term effects of guar gum on lipid metabolism after carotid endarterectomy. BMJ 1-14-1995;310:95-96. PubMed
Gylling, H., Riikonen, S., Nikkila, K., Savonius, H., and Miettinen, T. A. Oral guar gum treatment of intrahepatic cholestasis and pruritus in pregnant women: effects on serum cholestanol and other non-cholesterol sterols. Eur.J.Clin.Invest 1998;28(5):35 PubMed
Brillantino A, Iacobellis F, Izzo G, et al. Maintenance therapy with partially hydrolyzed guar gum in the conservative treatment of chronic anal fissure: results of a prospective, randomized study. Biomed Res Int 2014;2014:964942. PubMed
Polymeros D, Beintaris I, Gaglia A, et al. Partially hydrolyzed guar gum accelerates colonic transit time and improves symptoms in adults with chronic constipation. Dig Dis Sci 2014;59(9):2207-14. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Guar Gum and Mepolizumab Together: Common Questions

Is it safe to take Guar Gum with Mepolizumab?

We do not list a known interaction between Guar Gum and Mepolizumab. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.

Do Guar Gum and Mepolizumab have any of the same side effects?

Yes — our sources link each of them separately to 3 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.

Does Guar Gum interact with any other medications?

Yes. Guar Gum has 2,025 documented drug interactions in our database — Mepolizumab is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

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

Where next

Keep Exploring

Guar Gum monograph Uses, safety profile, and every drug interaction in one place Mepolizumab Injection drug information The full plain-English guide to this medication Mepolizumab supplement interactions Every supplement checked against Mepolizumab, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 26 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Mepolizumab and Guar Gum?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.