Aluminium hydroxide: Uses, dosing, side effects & safety

Aluminium hydroxide is an antacid you'll find in chewable tablets, liquids, and some combination products. It soaks up stomach acid fast and is also used by kidney patients to bind phosphate. If you're wondering when to reach for it and when to avoid it, here's a clear, practical guide.

As an over-the-counter antacid, aluminium hydroxide works within minutes to ease heartburn, indigestion, or sour stomach. For people with chronic kidney disease, doctors may prescribe it as a phosphate binder to lower blood phosphate levels. Those are two very different uses, so the dose and schedule change depending on why you take it.

How to take aluminium hydroxide safely

Follow the product label or your doctor's directions. For quick heartburn relief, chew the tablet or shake the liquid and swallow. For phosphate control, take the pills with meals so the drug binds phosphate from food. A simple rule: space aluminium hydroxide at least two hours away from other medicines that need acid or are affected by metal binding.

Common drug interactions include antibiotics like doxycycline and ciprofloxacin, thyroid medicine (levothyroxine), and iron supplements. These drugs can stick to aluminium and not be absorbed well. If you take any of those, plan your schedule or ask a pharmacist for exact timing.

Common side effects and who should avoid it

Constipation is the most common side effect. Some people switch to magnesium-containing antacids if that happens, but magnesium can cause diarrhea and isn't safe in kidney failure. In people with poor kidney function, aluminium can build up and cause bone problems or nervous system issues. That's why kidney disease needs a doctor's oversight.

Other warnings: long-term high-dose use may lead to low phosphate levels or contribute to bone weakness. Pregnant or breastfeeding people should check with their healthcare provider before using it regularly. Babies and small children need pediatric dosing — don't guess the dose.

Practical tips: use aluminium hydroxide for short-term heartburn relief or as prescribed for phosphate binding; read labels carefully; avoid combining with other metal-based antacids unless advised; and tell your doctor about all medicines and supplements you take. If symptoms persist for more than two weeks or you notice new muscle pain, bone pain, confusion, or severe constipation, get medical advice fast.

Buying online? Only use reputable pharmacies and verify credentials — fake or low-quality products may contain wrong doses or contaminants. Our site has articles on how to spot safe online pharmacies and on safe buying practices.

Example: if you take levothyroxine in the morning, wait four hours before using aluminium hydroxide. If using it for phosphate control, your clinic will monitor blood tests and adjust dose. Always keep a list of your meds for clinic visits.

Want one takeaway? Aluminium hydroxide works well when used the right way: correct dose, proper timing with meals and other drugs, and medical oversight if you have kidney disease. That keeps relief fast and side effects low. Ask questions — never assume safety.