Drug & supplement interaction

Citicoline + Lapatinib

Lapatinib brand name: Tykerb.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Citicoline 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. 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.

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Interaction report

Citicoline 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 Citicoline 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.

Worth understanding: our licensed dataset holds no drug-interaction record for Citicoline at all — not against Lapatinib, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

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.

Citicoline safety at a glance

Citicoline overall Use caution Generally well tolerated in studies, but long-term safety is not fully established.
Pregnancy Avoid Not enough safety data, so it is best to avoid during pregnancy.
Breastfeeding Avoid Not enough safety data, so it is best to avoid while breastfeeding.

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

Still wondering about combining Lapatinib and Citicoline? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Citicoline and Lapatinib 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.

  • Diarrhea / Nausea reported in 27.1% of FDA reports for Lapatinib Additional detail

    Citicoline

    “Orally, citicoline may cause abdominal pain, constipation, diarrhea, and nausea in some patients.”

    Citicoline · Natural Medicines adverse-effect record, reported in constipation.

    6 sources cited
    1. 12130. Spiers PA, Myers D, Hochanadel GS, et al. Citicoline improves verbal memory in aging. Arch Neurol 1996;53:441-8. PubMed
    2. 12132. Conant R, Schauss AG. Therapeutic applications of citicoline for stroke and cognitive function in the elderly: A review of the literature. Altern Med Rev 2004;9:17-31.
    3. 98846. Clark BC, Georgekutty J, Berul CI. Myocardial ischemia secondary to synthetic cannabinoid (K2) use in pediatric patients. J Pediatr 2015;167(3):757-61.e1. PubMed
    4. 100988. Ghajar A, Gholamian F, Tabatabei-Motlagh M, et al. Citicoline (CDP-choline) add-on therapy to risperidone for treatment of negative symptoms in patients with stable schizophrenia: a double-blind, randomized placebo-controlled trial. Hum Psychopharmacol. 2
    5. 105730. Castagna A, Manzo C, Fabbo A, Lacava R, Ruberto C, Ruotolo G. The CITIMERIVA Study: CITIcoline plus MEmantina plus RIVAstigmine in Older Patients Affected with Alzheimer's Disease. Clin Drug Investig. 2021 Feb;41(2):177-182. PubMed
    6. 109015. Jeong H, Yoon S, Sung YH, et al. Effects of cytidine-5'-diphosphate choline on gray matter volumes in methamphetamine-dependent patients: A randomized, double-blind, placebo-controlled study. J Psychiatr Res 2021;143:215-221. PubMed

    Lapatinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Lapatinib, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

  • A skin rash reported in 6.9% of FDA reports for Lapatinib Additional detail

    Citicoline

    Recorded for Citicoline in the same Natural Medicines adverse-effect record shown under Diarrhea / Nausea above.

    Lapatinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Lapatinib, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

Reported for Citicoline but not commonly for Lapatinib: stomach pain, blurred vision, constipation and a fast or pounding heartbeat.

Effects for Lapatinib come from the ADVERSE REACTIONS section of its FDA label; effects for Citicoline come from the Natural Medicines adverse-effect record, quoted above. 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. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Everything else you take

See Every Supplement That Interacts With Lapatinib

This page covers Citicoline 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

One more smart check

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

We hold 464 real supplement products containing Citicoline, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Citicoline. Even though Citicoline itself has no known interaction with Lapatinib, 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 Citicoline 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 Citicoline
Top 25%

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

29 days ago today
Medication Lapatinib
Steady interest

#1,780 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 Citicoline reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Citicoline and Lapatinib records this page draws on were last updated July 10, 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 .
Supplement

About Citicoline

What is Citicoline?

  • Memory and thinking
  • Brain health and aging
  • Stroke recovery support
  • Focus and attention
  • Eye health (glaucoma)

Citicoline is a naturally occurring compound involved in making brain cell membranes and the messenger chemical acetylcholine. It is popularly taken for memory, focus, and brain aging, and some research is promising, but high-quality evidence is still limited for most uses. It is generally well tolerated, but you should talk with your pharmacist or doctor before starting it.

Not applicable (a compound the body makes naturally) · Capsules, tablets, powder, sometimes liquid

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

Citicoline: dosing

There is no official standard dose of citicoline for supplement use. Doses used in research have varied widely depending on the condition being studied.The safest approach is to follow the directions on the product label and not exceed the recommended amount.

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

Read the full Citicoline monograph & all interactions
Medication

About Lapatinib

What Is Lapatinib Used For?

Brand name: Tykerb

Lapatinib tablets — sold under the brand name Tykerb — are used to treat advanced or metastatic breast cancer in patients whose tumors overexpress the HER2 protein. They are always used in combination with another medicine, not alone.

Tykerb is approved in combination with capecitabine for HER2-positive advanced or metastatic breast cancer in patients who have already received prior treatment including an anthracycline, a taxane, and trastuzumab, and whose disease has progressed on trastuzumab. Tykerb is also approved in combination with letrozole for postmenopausal women with hormone receptor-positive, HER2-positive metastatic breast cancer when hormonal therapy is appropriate.

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 & Citicoline

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

0Major
0Moderate
0Minor
2,829No known interaction
2,829 No interaction
No interaction 2,829 drugs checked — show the list

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

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Citicoline list.

See the full Citicoline interactions page
See every supplement checked against Lapatinib, ranked by severity
Evidence & sources

Citicoline References

The 11 references that drive our Citicoline 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.

  1. Spiers PA, Myers D, Hochanadel GS, et al. Citicoline improves verbal memory in aging. Arch Neurol 1996;53:441-8. PubMed
  2. Fioravanti M, Yanagi M. Cytidinediphosphocholine (CDP-choline) for cognitive and behavioural disturbances associated with chronic cerebral disorders in the elderly. Cochrane Database Syst Rev 2005;(2):CD000269. PubMed
  3. Conant R, Schauss AG. Therapeutic applications of citicoline for stroke and cognitive function in the elderly: A review of the literature. Altern Med Rev 2004;9:17-31.
  4. Warach, S., Pettigrew, L. C., Dashe, J. F., Pullicino, P., Lefkowitz, D. M., Sabounjian, L., Harnett, K., Schwiderski, U., and Gammans, R. Effect of citicoline on ischemic lesions as measured by diffusion-weighted magnetic resonance imaging. Citicoline 0 DOI
  5. Lukas, S. E., Kouri, E. M., Rhee, C., Madrid, A., and Renshaw, P. F. Effects of short-term citicoline treatment on acute cocaine intoxication and cardiovascular effects. Psychopharmacology.(Berl.) 2001;157(2):163-167. PubMed
  6. Dinsdale, J. R., Griffiths, G. K., Castello, J., Maddock, J., Ortiz, J. A., and Aylward, M. CDP-choline: repeated oral dose tolerance studies in adult healthy volunteers. Arzneimittelforschung. 1983;33(7A):1061-1065.
  7. Clark BC, Georgekutty J, Berul CI. Myocardial ischemia secondary to synthetic cannabinoid (K2) use in pediatric patients. J Pediatr 2015;167(3):757-61.e1. PubMed
  8. Ghajar A, Gholamian F, Tabatabei-Motlagh M, et al. Citicoline (CDP-choline) add-on therapy to risperidone for treatment of negative symptoms in patients with stable schizophrenia: a double-blind, randomized placebo-controlled trial. Hum Psychopharmacol. 2
  9. Castagna A, Manzo C, Fabbo A, Lacava R, Ruberto C, Ruotolo G. The CITIMERIVA Study: CITIcoline plus MEmantina plus RIVAstigmine in Older Patients Affected with Alzheimer's Disease. Clin Drug Investig. 2021 Feb;41(2):177-182. PubMed
  10. Jeong H, Yoon S, Sung YH, et al. Effects of cytidine-5'-diphosphate choline on gray matter volumes in methamphetamine-dependent patients: A randomized, double-blind, placebo-controlled study. J Psychiatr Res 2021;143:215-221. PubMed
  11. Nakazaki E, Mah E, Sanoshy K, Citrolo D, Watanabe F. Citicoline and Memory Function in Healthy Older Adults: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. J Nutr 2021;151(8):2153-2160. 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 Citicoline and Lapatinib Together: Common Questions

Is it safe to take Citicoline with Lapatinib?
We do not list a known interaction between Citicoline 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.
Do Citicoline and Lapatinib 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 Lapatinib interact with any supplements?
Yes. Lapatinib has documented interactions with 143 supplements in our database — Citicoline 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

Citicoline 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 11 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Lapatinib and Citicoline?

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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.