Drug & supplement interaction

Anhydrous Crystalline Maltose + Lapatinib

Lapatinib brand name: Tykerb.

No Known Interaction

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

The bottom line No known interaction

We found no known interaction between Anhydrous Crystalline Maltose and Lapatinib 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.

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Interaction report

Anhydrous Crystalline Maltose and Lapatinib

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 Lapatinib and Anhydrous Crystalline Maltose 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.

Anhydrous Crystalline Maltose safety at a glance

Anhydrous Crystall... overall Use caution Generally well tolerated in studies, but it is a sugar, so people with diabetes should be cautious.

Pregnancy Use caution Not well studied as a supplement in pregnancy; check with your doctor before use.

Breastfeeding Use caution Not well studied during breastfeeding; check with your doctor before use.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Lapatinib and Anhydrous Crystalline Maltose? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Lapatinib

Interactions in our licensed database are recorded against drug classes, not just single drug names. Lapatinib is filed under 3 classifications — cytochrome p450 3a4 (cyp3a4) inhibitors, cytochrome p450 3a4 (cyp3a4) substrates, oral drugs. Anhydrous Crystalline Maltose has documented interactions with 1 drug class — the most serious being antidiabetes drugs (minor) — and none of Lapatinib’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Anhydrous Crystalline Maltose Does Interact With Other Medications

Anhydrous Crystalline Maltose has 86 minor known drug interactions in our database — Lapatinib isn’t one of them. If you take anything else, check it against the full list below.

Minor 86 No known interaction 2,744 (incl. Lapatinib)

Taking anything else?

Check Another of Your Medications Against Anhydrous Crystalline Maltose

Covers the 2,830 medications we’ve checked against Anhydrous Crystalline Maltose. Pick one to open its full report.

What to actually watch for

What Lapatinib’s Own FDA Label Lists

This is not an interaction — none of it involves Anhydrous Crystalline Maltose. These are the most notable effects listed in the ADVERSE REACTIONS section of Lapatinib’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both.

Diarrhea mentioned in 27.1% of FDA reports for Lapatinib
Acne
Mouth irritation or sores
Tiredness mentioned in 8.5% of FDA reports for Lapatinib
Vomiting mentioned in 7.8% of FDA reports for Lapatinib
A skin rash mentioned in 6.9% of FDA reports for Lapatinib
Nausea mentioned in 10.5% of FDA reports for Lapatinib

From the ADVERSE REACTIONS section of the FDA label for Lapatinib. Read the label on DailyMed › Where a percentage is shown, it is the share of 15,427 voluntary FDA FAERS reports for Lapatinib that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Anhydrous Crystalline Maltose’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Anhydrous Crystalline Maltose side to compare — that is a limit of the record, not a statement that Anhydrous Crystalline Maltose has no side effects.

Everything else you take

See Every Supplement That Interacts With Lapatinib

This page covers Anhydrous Crystalline Maltose only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Lapatinib page lists 143 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 100 moderate · 40 minor.

From our pharmacist’s overview on the Lapatinib page

“Of the 143 supplements on file for lapatinib (Tykerb), nearly all press on the same point, the CYP3A4 enzyme that clears this HER2-targeted breast cancer drug. That deserves real caution, since lapatinib only works when its blood level stays in range.”

Reviewed by 2 · Jul 18, 2026

Open the Lapatinib interaction page

How much people look this up

Where Anhydrous Crystalline Maltose and Lapatinib 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 Anhydrous Crystalline Maltose

Steady interest

#1,211 of 1,452 supplements looked up here in the last 7 days

29 days ago today

Medication Lapatinib

Steady interest

#2,643 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 Anhydrous Crystalline Maltose reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Anhydrous Crystalline Maltose and Lapatinib records this page draws on were last updated June 22, 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 Anhydrous Crystalline Maltose

What is Anhydrous Crystalline Maltose?

Dry mouth (xerostomia)
Sjögren syndrome
Dry mouth from medications
Food stabilizer and texturizer

Anhydrous crystalline maltose is a starch-derived sugar (also called malt sugar) studied mainly as a slow-dissolving lozenge to ease dry mouth, including in people with Sjögren syndrome. Some studies suggest it may modestly improve saliva flow, but the overall evidence is limited. It appears generally well tolerated, but talk with your pharmacist or doctor before using it, especially if you have diabetes.

Disaccharide sugar derived from starch · Dissolving lozenges, tablets, powder

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

Anhydrous Crystalline Maltose: dosing

There is no official, standardized supplement dose for anhydrous crystalline maltose. Do not assume more is better.

From our Anhydrous Crystalline Maltose monograph — the full record covers uses, side effects and every documented interaction.

Read the full Anhydrous Crystalline Maltose monograph & all interactions

Medication

About Lapatinib

What Is Lapatinib Used For?

Brand name: Tykerb

Lapatinib tablets are used in combination with other medicines to treat certain types of advanced or metastatic breast cancer in patients whose tumors overexpress HER2 (a protein that drives tumor growth). It is not used alone.

Specifically, lapatinib tablets are used with capecitabine for HER2-positive advanced or metastatic breast cancer in patients who have already received prior therapy (including certain chemotherapy drugs and trastuzumab). Lapatinib tablets are also used with letrozole for postmenopausal women with hormone receptor-positive, HER2-positive metastatic breast cancer when hormonal therapy is appropriate. Tykerb is the brand name product with these same indicated uses.

Most-Reported Side Effects for Lapatinib

From FAERS, the FDA’s public side-effect reporting system (15,427 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 4,174 reports

Nausea 1,615 reports

Fatigue 1,305 reports

Vomiting 1,209 reports

Rash 1,061 reports

See full Lapatinib drug information

Keep checking

Other Drugs & Anhydrous Crystalline Maltose

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

0Major

0Moderate

86Minor

2,743No known interaction

86 Minor 2,743 No interaction

Minor

86 interactions

Showing 60 of 86 minor interactions — see all 86 on the Anhydrous Crystalline Maltose page.

No interaction 2,743 drugs checked — show the list

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

Showing the 60 most looked-up of 2,743 medications checked with no known interaction — see the full Anhydrous Crystalline Maltose list.

See the full Anhydrous Crystalline Maltose interactions page

See every supplement checked against Lapatinib, ranked by severity

Evidence & sources

Anhydrous Crystalline Maltose References

The 2 references that drive our Anhydrous Crystalline Maltose 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.

Fox, P. C., Cummins, M. J., and Cummins, J. M. Use of orally administered anhydrous crystalline maltose for relief of dry mouth. J Altern Complement Med 2001;7(1):33-43. PubMed
Fox, P. C., Cummins, M. J., and Cummins, J. M. A third study on the use of orally administered anhydrous crystalline maltose for relief of dry mouth in primary Sjogren's syndrome. J Altern Complement Med 2002;8(5):651-659.

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 Anhydrous Crystalline Maltose and Lapatinib Together: Common Questions

Is it safe to take Anhydrous Crystalline Maltose with Lapatinib?

We do not list a known interaction between Anhydrous Crystalline Maltose and Lapatinib. 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.

How was the Anhydrous Crystalline Maltose and Lapatinib combination checked?

Interactions in our licensed database are recorded against drug classes. Lapatinib is filed under 3 classifications, and Anhydrous Crystalline Maltose has documented interactions with 1 drug class — none of Lapatinib's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.

Does Anhydrous Crystalline Maltose interact with any other medications?

Yes. Anhydrous Crystalline Maltose has 86 documented drug interactions in our database — Lapatinib is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

Does Lapatinib interact with any supplements?

Yes. Lapatinib has documented interactions with 143 supplements in our database — Anhydrous Crystalline Maltose is not one of them. The Lapatinib interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Anhydrous Crystalline Maltose monograph Uses, safety profile, and every drug interaction in one place Lapatinib drug information The full plain-English guide to this medication Lapatinib supplement interactions Every supplement checked against Lapatinib, 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 2 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Lapatinib and Anhydrous Crystalline Maltose?

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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.