Can I take Gam and Shelcal together?
Drug interaction guide
Originally published 14 Mar 2026
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Taking these two together can make the gabapentin less effective. This means your nerve pain or seizures might not be as well-controlled as they should be.
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Why this happens
Shelcal contains calcium and vitamin D. Calcium acts as an antacid in the stomach. When taken at the same time, the calcium can bind to the gabapentin or change the stomach's acidity, which prevents the body from absorbing the full dose of gabapentin into the bloodstream.
What you should do
Back to contentsYou should separate the doses of these two medications. Take your gabapentin at least 2 hours after taking Shelcal. This gives your body enough time to absorb the gabapentin properly.
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Important precautions
Back to contentsKidney stones or severe kidney disease
Do not take this medicine if you have a history of kidney stones or severe kidney impairment, as it can lead to further stone formation or calcium build-up in the kidneys.
Hypercalcaemia (High blood calcium)
You must not take this if you have high levels of calcium in your blood or urine, as it can cause serious heart rhythm problems and kidney damage.
Food and drink warnings
Back to contentsDairy products
While Shelcal contains calcium, consuming very high amounts of dairy simultaneously can lead to 'milk-alkali syndrome' or excessively high calcium levels. However, for most patients, normal dietary intake is fine. It is often recommended to take calcium supplements with food to aid absorption.
Caffeine (Tea, Coffee, Cola)
Caffeine can slightly reduce the absorption of calcium and increase its excretion. Try to avoid taking your supplement at the same time as a large cup of tea or coffee.
High-fibre foods and Oxalates (e.g., Spinach, Rhubarb, Bran)
Foods very high in oxalic acid (spinach, rhubarb) or phytic acid (whole-grain cereals/bran) can bind to calcium and prevent it from being absorbed properly. Avoid taking Shelcal within 2 hours of eating these foods.
Alcohol
Chronic heavy alcohol consumption can interfere with how your body processes Vitamin D and absorbs calcium, potentially weakening bones over time. Moderate intake is generally acceptable.
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Using other medicines
Back to contentsTaking 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.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
14 Mar 2026 | Originally published

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