2. WHAT YOU NEED TO KNOW BEFORE YOU TAKE THIS MEDICINEDo not take Philips' Milk of Magnesia Liquid if you:- Are allergic to magnesium hydroxide or any of the other ingredients of this medicine (listed in section 6).- Have acute gastrointestinal conditions (conditions that affect your digestive tract and usually last for a short period of time).Warnings and precautions:Talk to your doctor or pharmacist before taking this 'medicine if:- You have kidney problems.- You are taking any other medicines (including those you bought yourself).- You are pregnant or breastfeeding.Check with you doctor if symptoms continue.Children: In small children use of magnesium hydroxide may cause increased amounts of magnesium in the blood (hypermagnesemia) particularly if they have kidney problems or are dehydrated.Other medicines and Philips' Milk of Magnesia Liquid:Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines.Some medicines may be affected by magnesium hydroxide or they may affect how well magnesium hydroxide will work:- Medicines to treat bacterial and fungal infections such as cefpodoxime, itraconazole, tetracyclines, ketoconazole and the quinolone group of antibacterials. Medicines use for viral infections (e.g. atazanavir, tipranavir, rilpivirine).Fexofenadine (an antihistamine commonly used for allergies). Bisphosphonates (used to help prevent or slow down bone thinning) such as alendronate, clodronate risedronate, ibandronic acid. Corticosteroids (anti-inflammatory medicines used for a wide range of conditions) such as deflazacort, dexamethasone. Digoxin (used for heart problems). Dipyridamole (blood thinner).Antiepileptics (gabepentin and phenytoin).Levothyroxine (used to treat underactive thyroid).Mycophenolate (mainly used to stop the body from rejecting a transplanted organ). Iron preparations (used to prevent and treat anemia caused by low iron levels). Rosuvastatin (used to treat high cholesterol levels). Antipsychotics (e.g. sulpiride, phenothiazines, chlorpromazine). Medicines to treat malaria such as chloroquine, hydroxychloroquine, proguanil. Penicillamine (anti-rheumatic). Ibuprofen (pain killer). Salicylates (such as aspirin). Dicoumarol (anticoagulant). Cimetidine (used to treat and prevent certain types of ulcer). Sodium polystyrene sulfonate (used to reduce high levels of potassium in the blood).Pregnancy and breast-feeding:If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.Driving and using machines:This medicine is unlikely to cause any effects on the ability to drive and use machines.4. Possible side effectsLike all medicines, this medicine can cause side effects, although not everybody gets them.Very rare side effects (may affect up to 1 in 10,000 people):- Hypermagnesemia (increased amount of magnesium in your blood). This was seen after prolonged administration to patients with kidney problems.Unknown side effects (frequency cannot be 'estimated from the available data):- Abdominal pain including colic.- DiarrhoeaReporting of side effectsIf you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report 'side effects directly via the Yellow Card Scheme via the website www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.By reporting side effects you can help provide more information on the safety of this medicine.