Herb & supplement monograph

Lobelia Drug Interactions, Uses, Effectiveness, Safety & More

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS ·Updated July 2026

What is this page for?

First and foremost: how Lobelia interacts with medications. The heart of this page is the interaction list — every drug Lobelia is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Lobelia is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy

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Lobelia Drug Interactions: The Bottom Line

From the HelloPharmacist Editorial Team · Updated July 2026

Based on the available evidence, the overall risk of a clinically significant Lobelia drug interaction appears low for most people, because only one medication interaction is known. That single interaction is rated moderate, not major, and no other medications are flagged.

Interactions deserving the most attention

The one combination that deserves real attention is lithium. Lobelia is thought to act as a diuretic, and anything that changes how the kidneys handle fluid can slow the removal of lithium from the body, allowing its levels to rise. Because lithium is a narrow-margin medicine that is closely monitored through blood tests, even a modest rise in levels can matter, so anyone taking it should treat this pairing seriously.

What the rest of the list means

Lobelia's interaction profile is unusually short, and short does not mean fully studied; it simply means only one concern has been documented so far. Even that concern rests partly on Lobelia's suspected diuretic effect rather than on large human trials, so it is a reasonable precaution rather than a proven harm. For people not taking lithium, the current data points to no known medication conflicts.

Check your medications against Lobelia

Based on HelloPharmacist’s Lobelia interaction data and reviewed under our editorial standards.

Interaction report

Drugs that interact with Lobelia

1 medication has a known interaction with Lobelia, graded by severity. Select any drug for the full evidence-based detail.

Don’t want to scroll the list? Just ask.

Tell us the medications you take and we’ll check each one against Lobelia using our pharmacist-reviewed interaction data.

AI summaries are generated from our Lobelia interaction data for education only — always confirm with your pharmacist. How we use AI

2,830 drugs

Read The List Like a Pharmacist

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
No known interaction. Checked against our sources with nothing documented — not the same as proven safety.

Likelihood — How Well It’s Documented

Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
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
Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Where This Data Comes From

Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
Each drug listed above links to the full report for that exact Lobelia combination — clinical detail, likelihood, evidence level, and citations.
Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

The big picture

The kinds of drugs Lobelia affects

Every type of medication (drug category) Lobelia is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 1 drug category Lobelia interacts with

Lithium

Lobelia is thought to have diuretic properties. Theoretically, due to these potential diuretic effects, lobelia might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D

Monograph

Lobelia: Uses, Safety & Side Effects

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Reviewed July 2026 ·

The bottom line

Lobelia is a traditional herb once used for breathing problems and to help people quit smoking, but reliable evidence supporting these uses is lacking. It can be toxic in higher amounts, causing serious side effects, so it should be used with great caution and only under professional guidance.

Scientific name: Lobelia inflata
Family: Campanulaceae
Part used: Dried aerial parts (leaves, stems, flowers, and seeds)
Common forms: Capsules, tinctures, liquid extracts, teas, and dried herb

People commonly use it for

Asthma and breathing problems
Cough and bronchitis
Smoking cessation aid
Muscle relaxation

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance

OverallUse caution

Lobelia can be toxic and cause serious effects at higher doses, so caution is strongly advised.

PregnancyLikely Unsafe

When used orally due to its emetic effects. There is insufficient reliable information available about the safety of lobelia when used topically durin...

Read the full pregnancy detail

BreastfeedingLikely Unsafe

When used orally due to its emetic effects. There is insufficient reliable information available about the safety of lobelia when used topically durin...

Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

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Overview

Lobelia (Lobelia inflata) is a flowering plant native to eastern North America. It is also sometimes called Indian tobacco because people once smoked or chewed the dried plant. The leaves, stems, flowers, and seeds have all been used in traditional and herbal medicine.

Historically, Native American and early American herbalists used lobelia for breathing problems such as asthma and bronchitis, as well as to cause vomiting. Today it is sold as capsules, tinctures, liquid extracts, and teas, often marketed as a remedy for coughs or as an aid to quit smoking.

How it works

The main active compound in lobelia is an alkaloid called lobeline. Lobeline is thought to act on nicotine receptors in the body, which is why it has been studied as a possible smoking aid and why lobelia has effects somewhat similar to nicotine.

At certain doses, lobeline may relax airways and stimulate breathing, but it can also stimulate the vomiting center in the brain, which is why lobelia was historically used to cause vomiting. Most of these mechanisms are based on laboratory and animal research, and the way they translate to real-world human benefits is not well established.

Effectiveness

Does Lobelia work?

Here’s what the research actually shows for each use — graded by Natural Medicines and reviewed by Dr. Brian Staiger, PharmD.

Evidence overview · 1 use evaluated

1 Leans ineffective

How to read these evidence grades

Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.

1EffectiveStrong, consistent evidence it works.

2Likely EffectiveGood evidence, though not yet conclusive.

3Possibly EffectiveSome evidence suggests a benefit.

4Possibly IneffectiveSome evidence it may not help.

5Likely IneffectiveFairly strong evidence it doesn’t help.

6IneffectiveStrong evidence it doesn’t work.

7Insufficient Reliable Evidence to RateToo little research to say either way.

Possibly Ineffective Smoking cessation

Rating & evidence shown verbatim from Natural Medicines

Some small clinical studies have evaluated the use of lobeline, a constituent of lobelia, for smoking cessation and stopping use of smokeless tobacco over a 48-hour period. These studies show inconsistent effects of lobelia on tobacco use, with many finding no benefit. The validity of these findings is limited by low study quality and the short duration of use.

Sources Ref 16413 Ref 16414 Ref 59987

Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.

Safety & precautions

Lobelia is considered potentially toxic, especially in larger amounts. Because its effects resemble nicotine, taking too much can lead to serious symptoms. For this reason, many experts recommend using lobelia only with caution and professional guidance.

People with heart disease, high blood pressure, a history of seizures, breathing problems, or stomach conditions should be especially careful and talk to a healthcare provider first. Children should not take lobelia.

Pregnancy and breastfeeding: Avoid lobelia if you are pregnant or breastfeeding. There is not enough safety information, and its toxic potential makes it a poor choice during these times.

Always talk with a pharmacist or doctor before using lobelia, particularly if you take medications or have a chronic health condition.

Side effects

Even at modest doses, lobelia can cause nausea, vomiting, dizziness, sweating, tremors, and a fast or irregular heartbeat. Many people find it unpleasant to take.

At higher or toxic doses, lobelia can cause more serious problems such as very low blood pressure, difficulty breathing, confusion, seizures, and in extreme cases, coma. Because of this narrow margin between a small dose and a harmful one, lobelia should be treated with great respect and caution.

Lobelia: Reported Adverse Effects

Documented safety reports on Lobelia from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.

Orally, lobelia can cause nausea, vomiting, diarrhea, coughing, dizziness, tremors, and throat irritation. These adverse effects have been reported with doses as low as 50 mg. Lobelia leaf can cause toxicity when taken in doses of 600 mg or higher. Symptoms of lobelia toxicity include sweating, tachycardia, convulsions, hypothermia, hypotension, coma, and death.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Stead LF, Hughes JR. Lobeline for smoking cessation. Cochrane Database Syst Rev 2000;2:CD000124.
Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.

Reports by condition

Diarrhea Gastrointestinal

Orally, lobelia can cause nausea, vomiting, diarrhea, and throat irritation.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Stead LF, Hughes JR. Lobeline for smoking cessation. Cochrane Database Syst Rev 2000;2:CD000124.

Hypotension Cardiovascular

Orally, high doses of lobelia leaf can cause toxicity. Symptoms of lobelia toxicity include tachycardia, hypotension, and death.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.

Myasthenia gravis Other

Orally, high doses of lobelia leaf can cause toxicity resulting in death. Toxicity has been reported to occur at doses as low as 600 mg, with doses of 4000 mg or more considered to be fatal.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.

Vertigo Neurologic/CNS

Orally, lobelia can cause dizziness and tremors. High doses of lobelia leaf can cause toxicity. Symptoms of lobelia toxicity include convulsions, coma, and death.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.

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.

Adverse-effects data: Natural Medicines, Therapeutic Research Center

Dosing

There is no well-established or standardized safe dose of lobelia. Because the plant can be toxic, the amount that helps and the amount that harms may be close together.

If a product is used, follow the directions on the label carefully and do not exceed them. It is best to speak with a pharmacist or doctor before starting lobelia so they can help you weigh the risks. We do not recommend self-dosing this herb without professional guidance.

Pregnancy & Breastfeeding

Lobelia & Pregnancy

Likely Unsafe

When used orally due to its emetic effects. There is insufficient reliable information available about the safety of lobelia when used topically during pregnancy and lactation.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.

Lobelia & Breastfeeding

Likely Unsafe

When used orally due to its emetic effects. There is insufficient reliable information available about the safety of lobelia when used topically during pregnancy and lactation.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.

Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center

References & further reading

The 6 references that drive our Lobelia 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.

Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
McChargue DE, Collins FL Jr, Cohen LM. Effect of non-nicotinic moist snuff replacement and lobeline on withdrawal symptoms during 48-h smokeless tobacco deprivation. Nicotine Tob Res 2002;4:195-200. PubMed
Stead LF, Hughes JR. Lobeline for smoking cessation. Cochrane Database Syst Rev 2000;2:CD000124. PubMed
Plakun, A. L., Ambrus, J., Bross, I., Graham, S., Levin, M. L., and Ross, C. A. Clinical factors in smoking withdrawal: preliminary report. Am J Public Health Nations.Health 1966;56(3):434-441. PubMed

Keep reading

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.

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.

Brand directory

Brands that make products with Lobelia

59 brands in our database make a supplement containing Lobelia.

Arise & Shine 16 products BIOVEA 1,494 products California Natural 23 products Catie's 23 products Cedar Bear 69 products Christopher's Original Formulas 140 products Crystal Star 123 products Doctor Morse's Healing Herbs 47 products Dr. Christopher's Original Formulas 14 products Dr. Morse's Cellular Botanicals 79 products Dr. Schulze's 11 products Earth Friend Herb Co. 66 products Eclectic Herb 284 products Eclectic Institute 125 products Energique 31 products Gaia Herbs Professional Solutions 145 products Gaia Herbs SystemSupport 60 products GHC Global Healing Center 32 products Global Healing 41 products Global Healing Center 98 products Harmonic Innerprizes 118 products Hawaii Pharm 4,726 products Herb Pharm 3,320 products Herb Stop 193 products

Product directory

Supplement products with Lobelia

482 products in our database contain Lobelia. Open any to see its full ingredient list and every drug interaction we check.

Pharmacist Counseling Corner

Lobelia: Common Questions

What is Lobelia used for, and does it work?

People use Lobelia for a range of reasons, but according to the Natural Medicines database the current clinical evidence is insufficient to confirm it works for the specific conditions it has been studied for. See the graded list on this page, and talk to your pharmacist or doctor before relying on it for any condition.

Does Lobelia interact with prescription medications?

Yes. We list 1 medication with a known interaction with Lobelia. Use the checker above to see how Lobelia interacts with a specific drug.

How are Lobelia interactions rated?

Each interaction is graded major, moderate, or minor based on how clinically significant it is and the strength of the evidence behind it. Major interactions are the most serious and are best avoided, or used only under close professional supervision.

Is it safe to take Lobelia with my medications?

It depends on the specific medication. Some combinations are fine, while others call for monitoring, timing changes, or should be avoided. Check your exact drug above and confirm with your pharmacist or doctor before starting, stopping, or changing anything.

Where does this Lobelia interaction information come from?

Our interaction data is built on the Natural Medicines database — an evidence-graded reference for vitamins, herbs, and supplements — and is reviewed by licensed HelloPharmacist pharmacists, who may add clinical context.

What is Lobelia used for?

Lobelia has traditionally been used for asthma, coughs, bronchitis, and as an aid to quit smoking, but strong scientific evidence supporting these uses is lacking.

Is Lobelia safe to take?

Lobelia can be toxic, especially in larger amounts, and may cause nausea, vomiting, a fast heartbeat, and other serious effects. It should be used cautiously and ideally under the guidance of a healthcare professional.

Can I use Lobelia while pregnant or breastfeeding?

No. Because of its toxic potential and the lack of safety data, Lobelia should be avoided during pregnancy and breastfeeding.

Does Lobelia really help people quit smoking?

Although lobeline acts on nicotine receptors and has been studied for this purpose, well-designed studies have not shown that it reliably helps people stop smoking.

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

Keep exploring

Products that contain Lobelia

A rotating sample of real supplements in our database that list Lobelia — open any to see its full ingredients and every drug interaction we check.

See all 482 products with Lobelia →

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