What Medicines Should You Not Take with Wegovy?

What Medicines Should You Not Take with Wegovy? A Complete Drug Interactions Guide

Medically reviewed by the Medetone Clinical Team Last updated: June 2026

If you're considering Wegovy (semaglutide) for weight loss through an online pharmacy like Medetone, one of the most important steps before starting treatment is understanding how it interacts with other medications. Most people take at least one other prescription or over-the-counter medicine, and knowing what's safe - and what isn't - helps your clinician make the right call for you.

This guide covers every major medication category: from blood pressure drugs and antidepressants to herbal supplements and ADHD medications. It also explains which combinations require additional monitoring, and which are straightforward.

Quick links:

How Wegovy Interacts With Other Medications

Wegovy works by mimicking GLP-1, a naturally occurring hormone that reduces appetite, slows how quickly the stomach empties, and helps regulate blood sugar. Unlike many medications, it doesn't significantly alter how oral drugs are absorbed through the gut - the manufacturer's own data confirms that any effect on stomach-emptying is not usually clinically meaningful.

The interactions that genuinely matter fall into two groups:

Medications that also lower blood sugar (such as insulin and sulfonylureas), where combining the two can push glucose too low
Medications with a narrow therapeutic window - drugs where even small shifts in blood levels can tip into toxicity or loss of effect - that require regular blood monitoring a remote online pharmacy cannot adequately supervise

According to government guidance on GLP-1 medicines, patients should always disclose their full medication list before starting any GLP-1 weight loss injection. Clinical evidence for semaglutide's safety profile is well-established in the literature, including published research on its interaction profile.

Quick Reference: Wegovy Drug Interaction Table

Who Should Not Take Wegovy?

Before discussing individual drug interactions, it's worth covering absolute contraindications - situations where Wegovy is not appropriate regardless of other medications.

Wegovy is not suitable if you:

Are under 18 years old
Are pregnant, breastfeeding, or actively trying to conceive
Have a personal or family history of thyroid cancer or Multiple Endocrine Neoplasia type 2 (MEN-2)
Have a history of pancreatitis
Have severe digestive conditions such as gastroparesis, Crohn's disease, or ulcerative colitis
Have a history of gallstones (with an intact gallbladder)
Have diabetic retinopathy (diabetes-related eye disease)
Have type 1 diabetes
Have severe liver or kidney disease, or serious heart failure
Are undergoing active cancer treatment
Have a current or past eating disorder (excluding binge eating disorder)
Have a history of organ transplant, epilepsy, or porphyria

All of these are screened during the Medetone eligibility assessment. Your clinician reviews every answer before any treatment is approved.

Medications That Cannot Be Combined With Wegovy

Some medications require frequent, in-person blood monitoring that a remote online pharmacy cannot safely provide. If you currently take any of the following, weight loss treatment via Medetone would need to be managed in partnership with your GP or specialist:

Blood thinners: warfarin, acenocoumarol

Heart medications: digoxin, flecainide, propafenone, quinidine, procainamide, disopyramide

Immunosuppressants: tacrolimus, ciclosporin, everolimus, sirolimus, azathioprine

Mood stabilisers: lithium

Epilepsy medications: phenytoin, carbamazepine, lamotrigine, oxcarbazepine, valproic acid, sodium valproate, primidone, phenobarbital, ethosuximide, zonisamide

Antipsychotics: clozapine

Diabetes medications (requiring close monitoring): insulin, sulfonylureas (gliclazide, glimepiride, glipizide, tolbutamide, chlorpropamide), other GLP-1 receptor agonists prescribed for diabetes

Other weight loss medications: orlistat, Mounjaro (tirzepatide), Rybelsus (oral semaglutide), retatrutide

Other: methotrexate (for cancer or IBD), theophylline, isoprenaline

Important note: Some of these exclusions are indication-specific. Carbamazepine and lamotrigine, for example, are only excluded when prescribed for epilepsy - if you take them for pain or another condition, you may still be eligible. Similarly, methotrexate is only excluded when used for cancer or IBD. Your Medetone clinician will review the specific context during your assessment.

Medications That Are Safe to Take With Wegovy

Metformin

Metformin and Wegovy are frequently prescribed together, particularly for people managing type 2 diabetes or PCOS. Both can reduce blood sugar, so it's worth having your GP check your levels a few months after starting Wegovy to see whether your metformin dose needs adjusting.

Birth Control and Contraception

Wegovy does not reduce the effectiveness of any form of hormonal contraception. This includes combined pills (such as Microgynon, Rigevidon, and Yasmin), progestogen-only mini pills (such as Cerazette and Cerelle), the Mirena and copper coil, the implant, the injection, and barrier methods.

Contraception is strongly recommended for anyone of childbearing age while taking Wegovy, because the medication must be stopped at least two months before trying to conceive - it remains in the body for an extended period after the last dose.

Switching from Mounjaro to Wegovy? Worth knowing: Mounjaro can reduce how well the contraceptive pill is absorbed, which means a barrier method is needed for four weeks after starting and after each dose increase. Wegovy does not have this effect, so the pill alone is sufficient.

Blood Pressure Medications

Most blood pressure medications are compatible with Wegovy, including ACE inhibitors (ramipril, lisinopril), angiotensin receptor blockers (losartan, candesartan), beta blockers (bisoprolol, propranolol), and calcium channel blockers (amlodipine, felodipine).

As weight loss progresses on Wegovy, blood pressure naturally tends to fall - which is generally a positive outcome, but may mean your existing medication becomes stronger than needed. Let your GP know you've started Wegovy so they can monitor your readings and adjust your dose if necessary.

Levothyroxine and Thyroid Medications

Levothyroxine and its alternative liothyronine can be taken alongside Wegovy. Because levothyroxine has a narrow therapeutic window, a TSH blood test is recommended around eight weeks after starting Wegovy, and again eight weeks after you reach a stable dose. Some patients find it helpful to take levothyroxine on an empty stomach on a different day from their Wegovy injection.

Antidepressants and Anti-Anxiety Medications

Most antidepressants and anti-anxiety medications are compatible with Wegovy, including:

SSRIs: sertraline, citalopram, escitalopram, fluoxetine
SNRIs and atypicals: venlafaxine, mirtazapine
Beta blockers for anxiety: propranolol
Benzodiazepines: lorazepam, diazepam

Two things to keep in mind:

First, both antidepressants and Wegovy can cause nausea, diarrhoea, and fatigue - particularly early in treatment or after a dose change. The combination may make these side effects feel more noticeable during the adjustment period.

Second, Wegovy can cause a modest increase in resting heart rate (typically one to four beats per minute). For most people this is not significant, but if you have anxiety, it may feel more noticeable initially.

Contact the Medetone clinical team if your mood or mental wellbeing changes after starting Wegovy.

ADHD Medications

There are no documented pharmacological interactions between Wegovy and ADHD medications - including methylphenidate (Ritalin, Concerta, Equasym), dexamfetamine (Amfexa), lisdexamfetamine (Elvanse), atomoxetine (Strattera), and guanfacine (Intuniv).

The practical consideration is appetite suppression. Both ADHD medications and Wegovy reduce appetite, and the combined effect can be significant - particularly during the first few weeks or after a Wegovy dose increase. Monitor your food intake carefully. If your appetite drops to the point where eating feels very difficult, or you feel weak or lightheaded, speak to your prescriber.

HRT (Hormone Replacement Therapy)

Non-oral forms of HRT - including oestrogen gels (Oestrogel, Sandrena), patches (Evorel), sprays, and the Mirena coil - have no known interaction with Wegovy and are safe to continue.

Oral progesterone (such as Utrogestan) requires a little more attention. The British Menopause Society has noted that GLP-1 weight loss injections may affect how well oral HRT is absorbed. This matters specifically because progesterone in HRT protects the womb lining - if absorption is compromised, that protection may be reduced. If you take oral progesterone, discuss this with your GP or gynaecologist before starting Wegovy, and report any unexpected bleeding promptly.

TRT (Testosterone Replacement Therapy)

Wegovy and testosterone replacement therapy are compatible. This includes injectable testosterone (testosterone cypionate, enantate, Nebido) and topical forms (Testogel, Testavan, Tostran). Tadalafil and sildenafil, when prescribed alongside TRT for erectile function, are also fine to take with Wegovy.

Hair Loss Treatments

Finasteride, dutasteride, and minoxidil - whether oral or topical - can all be taken alongside Wegovy without interaction. Some patients notice increased hair shedding after starting a GLP-1 weight loss injection, but this is generally a temporary response to rapid weight change rather than a medication-specific effect. It typically resolves as weight stabilises.

Antibiotics

Common antibiotics, including amoxicillin, flucloxacillin, and other penicillins, are safe to take with Wegovy. Both Wegovy and antibiotics can cause nausea and digestive discomfort, so the two together may feel more unsettled than either alone. If side effects are significant in the days leading up to your next Wegovy dose, let your prescriber know.

Painkillers

Paracetamol is the first-choice painkiller with no interaction concerns
Ibuprofen and NSAIDs are fine for occasional use, but regular use can aggravate the stomach - particularly if you're already experiencing gut side effects from Wegovy
Co-codamol is compatible with Wegovy, though both can cause constipation; staying well hydrated and active helps manage this

Antihistamines

Antihistamines - both non-drowsy types (cetirizine, loratadine, fexofenadine) and sedating types (chlorphenamine, promethazine, diphenhydramine) - have no known interaction with Wegovy. Sedating antihistamines can compound the tiredness some people experience in early Wegovy treatment.

Herbal Supplements and Vitamins

Standard vitamins, protein powder, collagen, creatine, and fibre supplements are all compatible with Wegovy. Most common herbal supplements - including ashwagandha, lion's mane, and echinacea - are also fine.

Two supplements warrant a mention:

St John's Wort can accelerate how the liver metabolises certain medications. Its direct effect on semaglutide hasn't been formally studied, but disclosing it at your consultation allows your treatment to be appropriately monitored.

Ginseng and fenugreek can lower blood sugar in some individuals. On their own, this is unlikely to be problematic, but combined with metformin or another diabetes medication, they could push glucose levels too low. Signs of low blood sugar include shakiness, sweating, dizziness, and unusual hunger - contact the clinical team if you experience these.

Alcohol and Wegovy

Moderate alcohol consumption is not prohibited while taking Wegovy, but a few things are worth knowing:

Alcohol is calorie-dense and can temporarily stimulate appetite - both work against weight loss progress
Both Wegovy and alcohol can cause nausea, stomach discomfort, and dehydration; together, the effect can feel worse
As you lose weight, your tolerance to alcohol typically decreases - the same amount can affect you more strongly than before

What to Tell Your Clinician Before Starting

The Medetone eligibility assessment guides you through your medical history systematically, but having the following information ready makes the process more accurate:

All current prescription medications, including doses
Any over-the-counter medications you take regularly
Supplements, vitamins, and herbal products
Your full medical history, particularly any conditions listed in the contraindications section above
Whether you are pregnant, breastfeeding, or planning to conceive
Any upcoming surgery or procedures requiring sedation

Being thorough gives your clinician everything they need to make the right decision for your health.

Wegovy vs Mounjaro: Which Is Right for You?

Both Wegovy (semaglutide) and Mounjaro (tirzepatide) are GLP-1-based weight loss injections available through Medetone. They cannot be taken together, and each has a slightly different interaction profile - Mounjaro, for instance, can reduce contraceptive pill absorption in a way that Wegovy does not.

For a full clinical comparison of how these two medications work, their efficacy data, and how to decide between them, see our patient guide to weight loss medications.

Frequently Asked Questions

Can I switch from Mounjaro to Wegovy?

Yes. You cannot take both simultaneously, but switching is possible with clinical guidance. Complete an eligibility assessment at Medetone and your clinician will advise on timing and dosing for the transition.

Can I drink alcohol while taking Wegovy?

Yes, in moderation. Alcohol can slow weight loss and worsen Wegovy side effects like nausea. Your alcohol tolerance may also decrease as your weight changes.

Can I take orlistat and Wegovy together?

No. Combining two weight loss medications is not safe. If you are currently taking orlistat and want to switch to Wegovy, a Medetone clinician can guide you through the process.

Does Wegovy affect the contraceptive pill?

No. Studies confirm Wegovy does not reduce the effectiveness of combined or progestogen-only pills. This is different from Mounjaro, which can reduce pill absorption during the early stages of treatment.

Do I need to stop Wegovy before surgery?

Yes. If your surgery involves a general anaesthetic, you should stop Wegovy at least one week before the procedure. Always inform your surgical and anaesthetic team that you are on Wegovy before any operation.

When should I stop Wegovy if planning to become pregnant?

Stop Wegovy at least two months before trying to conceive. The medication remains in the body for an extended period after the last dose, and this gap is needed to clear it fully before pregnancy.

Start Your Weight Loss Journey With Medetone

Medetone is a trusted online pharmacy delivering clinically-supervised GLP-1 weight loss treatments - including Wegovy and Mounjaro - to patients across Europe, including the UK, France, Germany, Spain, Italy, the Netherlands, Belgium, Austria, and Switzerland.

Every treatment request is reviewed by a qualified clinician. Your full medication list and medical history are assessed before any prescription is issued, so you can start treatment with confidence.

Check your eligibility at Medetone →

This article is for informational purposes only and does not constitute medical advice. Always consult your prescriber or GP before making any changes to your medications.

References:

UK Government. GLP-1 Medicines for Weight Loss and Diabetes: What You Need to Know. gov.uk
PubMed. Clinical evidence for semaglutide in weight management. pubmed.ncbi.nlm.nih.gov/42225305
British Menopause Society. Use of Incretin-Based Therapies in Women Using HRT: Tool for Clinicians. thebms.org.uk
Faculty of Sexual & Reproductive Healthcare. GLP-1 Agonists and Contraception: Patient Information Leaflet. fsrh.org

What Medicines Should You Not Take with Wegovy? | Medetone