Jump to: When Foundayo can be used with an anticoagulant | Does Foundayo interact directly with anticoagulants? | Food, dose, and monitoring for each anticoagulant | When blood tests and medication reviews are needed | How food affects rivaroxaban and warfarin | Vomiting and missed doses | Bleeding warning signs | Surgery and dental treatment | Frequently asked questions | Take home message | References
You may be able to take Foundayo (orforglipron) with apixaban, rivaroxaban, edoxaban, dabigatran, or warfarin after an individual medication review.
The UK Foundayo prescribing information doesn’t list a direct interaction with these medicines.
However, none of the combinations has been tested directly, so a prescriber should still review the anticoagulant, dose, and monitoring plan.1
Rivaroxaban 15 mg and 20 mg must be taken with food.
Warfarin dosing is guided by INR, a blood test that measures how long blood takes to clot. Dosing requirements can change if there’s an increase in vitamin K intake.
Reviews for direct oral anticoagulants also use body weight and kidney function.
Important safety information: Foundayo and anticoagulants are prescription-only medicines. Never stop, skip, or change an anticoagulant because of Foundayo side effects without urgent advice from your GP, anticoagulation service, or pharmacist. Missing anticoagulant doses can increase the risk of a blood clot or stroke.
When Foundayo can be used with an anticoagulant
You may be able to take Foundayo with an anticoagulant after your prescriber reviews why it was prescribed, the exact medicine and dose, kidney and liver function, and any recent change in weight.
Foundayo reduces hunger and food noise, allowing those on the drug to eat smaller portions and lose weight. It can also cause nausea, vomiting, and diarrhoea, particularly during dose increases.1
Our guide to Foundayo side effects gives the trial rates by dose and the warning signs that need medical advice.
Rivaroxaban 15 mg and 20 mg must be taken with food, so reduced appetite or vomiting can affect how these doses are taken.
Warfarin dosing may need review if Foundayo causes a lasting change in diet, vomiting, or diarrhoea.
Direct oral anticoagulants, or DOACs, don’t usually require routine INR tests. They still need reviews of kidney function, liver function, weight, bleeding, and whether doses are being taken as prescribed.2
Warfarin requires regular INR monitoring. Diet changes, illness, diarrhoea, vomiting, or a new medicine can affect results, so the anticoagulation service may arrange additional tests.
Does Foundayo interact directly with anticoagulants?
The UK Foundayo prescribing information doesn’t report a direct interaction study with apixaban, rivaroxaban, edoxaban, dabigatran, or warfarin.
Orforglipron (the drug in Foundayo) didn’t change CYP3A or P-glycoprotein activity enough to affect other medicines. CYP3A is a liver enzyme, and P-glycoprotein helps move medicines through cells.1
CYP3A and P-glycoprotein help the body process several direct oral anticoagulants, so the findings reduce concern about a major direct interaction.
Still, no study has measured anticoagulant levels or effects when these medicines are taken with Foundayo.
Foundayo delays stomach emptying, which can affect how the body absorbs other oral medications.
In one study, orforglipron reduced paracetamol’s peak blood level by 28%. The UK licensing assessment concluded that this wouldn’t affect how common oral medicines work overall.1
However, the assessment didn’t cover anticoagulants. Vomiting can prevent a dose from being fully absorbed, and rivaroxaban 15 mg or 20 mg may not be absorbed properly without food.4
Tests suggest that orforglipron doesn’t block or increase CYP2C9, one of the liver enzymes that processes warfarin, enough to affect how the medicine works. INR testing is still needed to judge which warfarin dose is right for you.1
Food, dose, and monitoring for each anticoagulant
| Anticoagulant |
Food and monitoring |
What to check when taking Foundayo |
| Apixaban |
Can be taken with or without food. No routine INR testing. |
For atrial fibrillation, the lower dose applies when at least two of these are present: age 80 or older, weight 60 kg or less, or serum creatinine of 133 micromol/L or higher. Serum creatinine is a kidney blood test.3 |
| Rivaroxaban |
The 15 mg and 20 mg doses must be taken with food. No routine INR testing.4 |
Double-check with your prescriber whether your reduced portion sizes are sufficient to take rivaroxaban alongside them. Don’t take these doses fasting. |
| Edoxaban |
You can take it with or without food. Factors influencing the correct dose include kidney function, body weight, and interacting medicines. |
Ask for a review if your weight reaches 60 kg or less, rather than changing the dose yourself.2 |
| Dabigatran |
No routine INR testing. Kidney function will determine the correct dose. |
Dehydration from persistent vomiting or diarrhoea needs prompt review because it can affect kidney function. |
| Warfarin |
Regular INR tests guide the dose. Keep vitamin K intake reasonably consistent.5 |
Tell the anticoagulation service if Foundayo causes a lasting change in diet, vomiting, or diarrhoea. |
The apixaban criteria above apply to preventing strokes in people with atrial fibrillation.
Dosing requirements are different when apixaban is used to treat or prevent blood clots in the legs or lungs.3
When blood tests and medication reviews are needed
Before starting Foundayo, confirm that your anticoagulant review is up to date. The usual DOAC checks include a full blood count, kidney function, liver function, body weight, and signs of bleeding.2
Once a DOAC is stable, these checks are generally repeated at least annually.
More frequent monitoring may be needed if you’re over 75, frail, have reduced kidney function, start an interacting medicine, or develop an illness that affects the kidneys or liver.2
Clinicians use current body weight when calculating kidney function for direct oral anticoagulant decisions. Ask for a review after a substantial weight change rather than waiting for the next annual appointment.2
If you take warfarin, ask the anticoagulation service whether you need an INR blood test after starting Foundayo or after a dose increase.
There’s no fixed schedule for these extra tests. Your previous INR results, food intake, and side effects determine how often you need them.
Keep a current list of both medicines and carry your anticoagulant alert card.
How food affects rivaroxaban and warfarin
Foundayo doesn’t need to be taken on an empty stomach and can be taken at any time of day, with or without food. Keep taking the anticoagulant at its usual time and choose a separate convenient time for Foundayo.1
For rivaroxaban 15 mg or 20 mg, continue taking the tablet with a meal. Food increases absorption of the 20 mg dose and is part of the licensed directions.4
If your appetite is low, we still recommend eating meals based on whole foods, even if the portion size is smaller.
You could try meals that are easier to digest, such as eggs with wholegrain toast and tomatoes, Greek yoghurt with oats and berries, or bean and chicken soup can provide protein, fibre, and complex carbohydrates without requiring a large meal.
If you take warfarin, don’t remove green vegetables from your diet because they contain vitamin K. General advice is to avoid making significant, sudden changes in vitamin K intake.5
Try to eat a similar amount of vitamin K across the week. If you regularly ate spinach, broccoli, or other green vegetables, we recommend maintaining that intake while on Foundayo.
You should also avoid starting vitamin K supplements without advice. Tell the prescriber about herbal remedies too, because some can interact with Foundayo or an anticoagulant.
Heavy alcohol use can increase bleeding risk and worsen nausea or dehydration from Foundayo. Follow the limit agreed with your anticoagulation service and avoid binge drinking.
Vomiting and missed doses
If you vomit after taking your anticoagulant medication, you may not know whether enough medicine was absorbed or whether the dose should be repeated.
There isn’t one safe rule for every anticoagulant in this scenario. We recommend calling your anticoagulation service, pharmacist, GP, or NHS 111 and telling them the medicine, dose, time taken, and when you became ill.
Don’t take a replacement dose unless they advise it. Taking too little may leave you unprotected from a clot; taking two doses may increase bleeding.
Contact your Foundayo prescriber if vomiting or diarrhoea is persistent. The next dose increase can be delayed, and the current dose may need review.1
Bleeding warning signs
Foundayo isn’t an anticoagulant, and bleeding isn’t listed among its side effects in the UK prescribing information. The anticoagulant you’re taking can still cause serious bleeding.1
Get urgent medical help for blood in your urine, red or black stools, vomiting or coughing blood, severe unexplained bruising, sudden severe back pain, breathing difficulty, chest pain, or a nosebleed lasting longer than ten minutes.6
Seek immediate advice after a major accident, fall or blow to the head, even if you initially feel well.
Surgery and dental treatment
Tell the dentist, surgeon, and anaesthetist that you take both Foundayo and an anticoagulant.
Anticoagulant doses sometimes need adjusting before a procedure, but this depends on the procedure and why the medicine was prescribed. Never pause an anticoagulant based on general online advice.
Foundayo delays stomach emptying, and aspiration, when food or fluid enters the lungs, has been reported with GLP-1 medicines during general anaesthesia or deep sedation. The anaesthetic team should decide what to do before the procedure.1
Frequently asked questions
Can I take Foundayo with apixaban?
The Foundayo licence doesn’t list a direct interaction with apixaban, but the combination hasn’t been tested directly.
Ask for a review of kidney function, body weight, the reason for apixaban, and the current dose.1-3
Can I take Foundayo with rivaroxaban?
Foundayo may be used with rivaroxaban after a medication review. Keep taking 15 mg or 20 mg rivaroxaban with food.4
Can I take Foundayo with warfarin?
No direct interaction is listed, but warfarin is sensitive to changes in diet, illness, and other medicines. Tell the anticoagulation service before starting Foundayo and ask whether you need extra INR tests.1,5
Do I need to avoid broccoli or spinach?
You don’t need to avoid broccoli or spinach if you take warfarin. Eat a reasonably consistent amount of vitamin K rather than removing nutritious green vegetables from your diet.5
DOACs such as apixaban and rivaroxaban don’t have the same vitamin K interaction.
Will losing weight change my anticoagulant dose?
Losing weight can prompt a medication review, but it doesn’t mean the anticoagulant dose should automatically fall. The dose rules depend on the medicine and why it was prescribed.
Do I need regular blood tests on a DOAC?
DOACs don’t use routine INR tests, but they still require regular kidney and liver function tests, blood counts, and medication reviews.
For most people taking a stable dose, these checks happen at least once a year. People at higher risk need more frequent checks.2
Take home message
Foundayo may be used with apixaban, rivaroxaban, edoxaban, dabigatran, or warfarin after an individual medication review.
The UK Foundayo prescribing information lists no direct interaction, but these combinations haven’t been tested directly.
Keep taking rivaroxaban 15 mg or 20 mg with food, maintain consistent vitamin K intake on warfarin, and report vomiting or a substantial weight change to your prescriber.
Don’t change an anticoagulant dose on your own. The prescriber or anticoagulation service should base any change on the medicine, why it was prescribed, kidney function, weight, and relevant blood tests.
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