Phosphate Binder (Lanthanum-Based) Pregnancy: There are no adequate data in pregnant women; one rat study showed reproductive foetotoxicity (delayed eye opening and sexual maturation) and reduced pup weights at high doses, and the potential risk for humans is unknown — Fosrenol is not recommended for use during pregnancy. Breast-feeding: it is unknown whether lanthanum is excreted in human breast milk (not studied in animals) — caution is required when deciding whether to continue breast-feeding or therapy. No human fertility data; no adverse effects on fertility in rat studies.

Lanthanum Carbonate 750mg–3g/day (Fosrenol)

Brand names: Fosrenol

Lanthanum carbonate (Fosrenol) is a non-calcium, non-aluminium phosphate-binding agent taken with meals to lower serum phosphate in patients with chronic kidney disease, especially those on dialysis.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Control of serum phosphate has been demonstrated at doses starting from 750 mg per day; the dose is titrated every 2 to 3 weeks against serum phosphate until an acceptable level is reached. Patients who respond usually achieve acceptable serum phosphate levels at 1500 mg to 3000 mg lanthanum per day.

Route: Oral — tablets must be chewed completely and not swallowed whole (they may be crushed to aid chewing). Where Fosrenol oral powder is available it can replace chewable tablets in patients who have difficulty chewing.

Frequency: Daily dose divided between meals, taken with or immediately after food

Max: No licensed maximum is stated; the maximum dose studied in clinical trials, in a limited number of patients, was 3750 mg.

Source: UK SPC (eMC) for Fosrenol 1000 mg chewable tablets, §4.2 (https://www.medicines.org.uk/emc/product/7494/smpc). Applies to adults including the elderly (> 65 years). Serum phosphate levels should be monitored and the dose titrated every 2 to 3 weeks until an acceptable serum phosphate level is reached, with regular monitoring thereafter. Patients should adhere to recommended diets to control phosphate and fluid intake; the chewable presentation avoids the need for additional fluid. SAFETY: tablets must be chewed completely and not swallowed whole to reduce the risk of serious gastrointestinal complications — cases of gastrointestinal obstruction, ileus, subileus and perforation have been reported, some requiring surgery or hospitalisation. Use only after careful consideration in patients predisposed to obstruction/ileus/perforation (altered GI anatomy such as diverticular disease, peritonitis, previous GI surgery, GI cancer or ulceration; hypomotility disorders such as constipation or diabetic gastroparesis; concomitant medicines known to potentiate these effects). Withdrawal is recommended in patients who develop severe constipation or other severe gastrointestinal signs and symptoms. Lanthanum deposition in gastroduodenal mucosa has been reported, mainly after long-term use. Fosrenol does not contain calcium — monitor serum calcium at regular intervals in patients with renal insufficiency, who may develop hypocalcaemia, and give appropriate supplements. HEPATIC IMPAIRMENT: the effect has not been assessed; because of its mechanism of action and lack of liver metabolism, doses should not be modified, but patients should be monitored carefully. PAEDIATRIC: safety and efficacy below 18 years have not been established and no recommendation on posology can be made — verify any under-18 use against a children's formulary. §4.4 was truncated at the source-fetch limit and §4.5 interactions was not retrieved in this bundle.

Dose adjustments

Renal

No renal dose adjustment is stated — the product is a phosphate binder used in renal patients and the dose is titrated against serum phosphate. §4.4 notes that patients with renal insufficiency may develop hypocalcaemia and that, as Fosrenol contains no calcium, serum calcium should be monitored at regular intervals with appropriate supplements given.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients
Hypophosphataemia
Bowel obstruction

Side effects

Very common: abdominal pain, diarrhoea, nausea, vomiting; headache
Common: constipation, dyspepsia, flatulence; hypocalcaemia
Uncommon: ileus, subileus, intestinal obstruction, irritable bowel syndrome, oesophagitis, stomatitis, dry mouth; rare intestinal perforation
Uncommon metabolic/endocrine: hypercalcaemia, hyperphosphataemia, hypophosphataemia, hyperglycaemia, hyperparathyroidism, anorexia or increased appetite
Uncommon: dizziness, taste alteration, vertigo, alopecia, increased sweating, arthralgia, myalgia, osteoporosis, asthenia, fatigue, peripheral oedema
Post-marketing: allergic skin reactions including rash, urticaria and pruritus; raised blood aluminium, GGT, transaminases and alkaline phosphatase; transient QT changes (not associated with an increase in cardiac adverse events)

Clinical monograph

How it works

It releases lanthanum ions in the upper gastrointestinal tract that bind dietary phosphate to form insoluble lanthanum phosphate, which is then excreted and not absorbed.

Prescribing in practice

The chewable tablets must be chewed completely and taken with or just after food; swallowing them whole reduces efficacy and has been linked to gastrointestinal injury and obstruction.
Use with caution in conditions predisposing to gut obstruction, ileus or impaction, as serious gastrointestinal events have been reported.
Administer other oral drugs that may be chelated at a separate time from the binder.

Monitoring

Check serum phosphate regularly, alongside calcium, to titrate to target and prevent excessive lowering.

Counselling the patient

Chew each tablet thoroughly and take it with food to make it work and protect your gut.
Tell your team about severe constipation, abdominal pain or any vomiting.
Space other medicines away from your phosphate binder as instructed.

Evidence & guidelines

Guidance on chronic kidney disease-mineral and bone disorder supports lanthanum carbonate as an effective non-calcium phosphate binder.

Reference: KDIGO CKD-MBD Guidelines 2017; Fosrenol SPC; NICE TA117; Confirm identity and dosing against the manufacturer SPC (eMC) and NICE. Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways