Can I take Omeprazole and Simvastatin together?

You can take omeprazole and simvastatin together, but with medical supervision.

If you experience any unexplained muscle pain, tenderness, or weakness, contact your doctor immediately. Your doctor may choose to limit your simvastatin dose to 20mg or 40mg daily, or monitor you more closely.

Why this happens

Both drugs are processed by the same enzymes in the liver. Omeprazole can slow down the breakdown of simvastatin, leading to higher levels of the statin remaining in your body.

How to know if you're having a drug interaction

You may be experiencing an interaction between omeprazole and simvastatin if:

• You develop new or worsening muscle pain, tenderness, or weakness.

• You feel unusually tired or weak without a clear reason.

• You notice dark-coloured urine.

• You experience nausea or upper abdominal discomfort.

• Blood tests show raised muscle enzymes (CK levels) or changes in liver function.

• Symptoms start after starting omeprazole or increasing the dose while taking simvastatin.
  

What you should do

If you have any of the above symptoms, you should:

• Contact your GP or pharmacist for advice as soon as possible.

• Do not stop taking simvastatin suddenly unless advised by a healthcare professional.

• Seek urgent medical help if you develop severe muscle pain, weakness, or dark urine.

• Attend any blood tests arranged to check muscle enzymes or liver function.

• Tell your healthcare professional about all medicines and supplements you are taking.

Important precautions

Pregnancy

You must not take simvastatin if you are pregnant, planning to become pregnant, or breastfeeding, as it may harm the developing baby. Use effective contraception while taking this medicine.

Muscle problems (Myopathy/Rhabdomyolysis)

Report any unexplained muscle pain, tenderness, or weakness to your doctor immediately. This risk is significantly increased if simvastatin is taken with certain other medicines (such as clarithromycin or erythromycin) or large amounts of grapefruit juice.

Severe diarrhoea

Contact your doctor immediately if you develop severe or persistent watery diarrhoea, as omeprazole can increase the risk of a serious bowel infection called Clostridium difficile.

Vitamin B12 deficiency

Long-term use of omeprazole can prevent your body from absorbing Vitamin B12 properly, which may lead to nerve damage or anaemia.

Lupus (SLE)

Seek medical advice if you develop a skin rash, especially in areas exposed to the sun, as omeprazole can trigger or worsen a rare autoimmune condition called Subacute Cutaneous Lupus Erythematosus.

Food and drink warnings

Alcohol

It is best to avoid or strictly limit alcohol while taking these medicines. For simvastatin, heavy drinking increases the risk of liver problems and muscle pain. For omeprazole, alcohol can increase stomach acid production, making your symptoms worse and irritating your stomach lining.

Grapefruit juice

You must avoid drinking grapefruit juice or eating grapefruit while taking simvastatin. Grapefruit contains compounds that significantly increase the level of simvastatin in your blood, which greatly increases your risk of serious side effects, such as muscle damage (rhabdomyolysis).

General Food Timing

Omeprazole works best if you take it 30 to 60 minutes before a meal, preferably breakfast. Taking it with food can slow down how quickly the medicine starts to work.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.