Co-amilofruse

Legal status and availability in the UK

Co-amilofruse is a prescription-only medicine (POM) in the UK.

In our online pharmacy, co-amilofruse is available without a prescription, with discreet delivery to the United Kingdom in 9–21 days.

Basic co-amilofruse information

• INN (international nonproprietary name): Furosemide (frusemide) and amiloride hydrochloride
• Brand names available in the United Kingdom: Frumil 40mg/5mg — tablets, blister packs; orange with break-line and “FRUMIL” on reverse.
• ATC code: C03EB01.
• Forms and dosages: Tablet — 40 mg furosemide + 5 mg amiloride, oral, scored for splitting
• Manufacturers in the United Kingdom: Sanofi (Frumil)
• Registration status in the United Kingdom: Licensed by the MHRA; prescription-only medicine
• OTC / Rx classification: Prescription-only medicine (POM)

Product basics and composition

INN, ATC, form and strengths

Co-amilofruse combines the INNs furosemide (frusemide) and amiloride hydrochloride, pairing a loop diuretic with a potassium-sparing agent.

The WHO/ATC classification for the combination is C03EB01, denoting potassium-sparing plus other diuretics.

The product is sold as oral tablets in the standard strength of 40 mg furosemide with 5 mg amiloride and the tablet is scored for splitting.

The originator manufacturer is Sanofi.

Regulatory status in the United Kingdom is Prescription Only Medicine (POM) with the SPC and PIL publicly accessible via MHRA-linked resources.

Packing typically comprises orange tablets in blister packs or pharmacy bottles, the tablets bearing a break-line and “FRUMIL” on one side.

Indications and typical clinical use

Typical use and regimens

Patients commonly use co-amilofruse to reduce fluid overload rather than as first-line treatment for high blood pressure.

Typical indications include oedema due to heart failure, hepatic causes or renal causes where fluid removal is required and a potassium-sparing effect is desirable.

Co-amilofruse is not used as first-line monotherapy for uncomplicated hypertension; this is not its primary indication.

Standard adult dosing starts with one tablet (40 mg/5 mg) each morning, with an option to increase to two tablets per day divided between morning and noon if needed.

The maximum amiloride dose is 20 mg per day, which corresponds to a maximum of four tablets daily; dosing must be titrated to response and tolerance.

Treatment duration is determined by the clinical condition — for heart failure and persistent oedema treatment may continue while clinically indicated.

If stopping treatment, tapering or supervised cessation is advised rather than abrupt discontinuation where clinically appropriate.

How to take and practical dosing tips

Splitting tablets, timing, missed doses and day-to-day advice

Co-amilofruse is usually taken in the morning to reduce the chance of nocturia and the tablet is scored so it can be split for dose adjustment.

The tablet can be taken with or without food according to tolerance; no special meal timing is required for absorption.

If a dose is missed, patients should take it when remembered unless it is close to the time of the next dose — they should not double up.

Standing up slowly from sitting or lying helps reduce orthostatic dizziness, a common issue especially at the start of therapy.

Patients who travel or work shifts should plan dosing around toilet access and breaks, taking doses earlier in their waking day where possible.

Carrying a medication card that lists the active ingredients helps with travel and in an emergency.

Check with your prescriber before adjusting fluid intake or taking potassium supplements without guidance.

Contraindications and cautions

Absolute contraindications and situations requiring close monitoring

Certain conditions make co-amilofruse unsuitable or risky.

Absolute contraindications include anuria, severe renal failure, hyperkalaemia, Addison’s disease, and known allergy to furosemide, amiloride, sulfonamides or sulfonylureas.

Pregnancy and breastfeeding require specialist review and a careful risk–benefit assessment before use.

Relative contraindications where caution and monitoring are needed include diabetes, gout, mild to moderate renal or hepatic impairment, and elderly patients with multiple comorbidities.

Rising creatinine, persistent dizziness or unrecorded hyperkalaemia need GP or specialist review.

Only pause the medicine on clinician instruction, and seek prompt review rather than stopping abruptly in most cases.

Side effects and patient-reported issues

Common, less common and warning signs

Patients need straightforward information on what to expect and which signs require action.

Common effects include increased urination, mild dehydration and dizziness particularly when standing up.

Electrolyte disturbances such as low potassium (hypokalaemia) or low sodium (hyponatraemia) can occur and may present as weakness or cramps.

Gastrointestinal upset such as nausea or mild abdominal discomfort is reported by some patients.

Blood-test changes including raised cholesterol, triglycerides and liver enzymes have been documented and should be monitored according to the prescriber.

Rare but serious hypersensitivity reactions or severe rash require immediate medical attention and stopping the medicine.

Report significant dizziness, muscle weakness, fainting or sudden swelling straightaway, and carry a brief medication card noting the co-amilofruse composition.

Side effects can be reported via the national Yellow Card scheme; return for review if symptoms persist or worsen.

Interactions and medicines to check

Key drug interactions and OTC checks

Co-amilofruse interacts with several commonly used medicines and over-the-counter preparations, so a medicines check is essential at supply.

High-priority interactions include potassium supplements and potassium-sparing agents, ACE inhibitors and ARBs, NSAIDs, digoxin and lithium — these can affect potassium levels or renal function.

Concurrent use with SSRIs or certain antibiotics may increase the risk of electrolyte disturbance and should prompt monitoring.

Avoid unregulated herbal or OTC supplements that contain potassium unless recommended and supervised by a clinician.

With multiple antihypertensives or diuretics, the cumulative effects on blood pressure and electrolytes should be checked.

Monitoring: blood tests, blood pressure and weight

Baseline checks and ongoing schedules

Monitoring is a core safety requirement for patients on co-amilofruse.

Baseline renal function and electrolytes should be checked before or at initiation where possible.

Repeat blood tests soon after starting or after a dose change — commonly within one to two weeks — then schedule ongoing checks depending on stability and comorbidity.

Blood pressure should be assessed regularly and patients with heart failure are advised to monitor body weight daily at home to detect fluid changes early.

Elderly patients and those with renal impairment usually need closer follow-up and shorter monitoring intervals.

The GP should be contacted if tests are overdue or abnormal.

Special populations: elderly, renal impairment, children

Dose adjustments and safety notes

Counselling and dose decisions vary with age and organ function and should always be individualised.

Elderly patients generally require a “start low and go slow” approach because of altered fluid balance and higher comorbidity burdens.

Co-amilofruse is contraindicated in severe renal failure and anuria; in mild to moderate renal impairment use with caution and intensify electrolyte and renal monitoring.

Children are not commonly treated with this combination except under specialist supervision because of limited paediatric data.

Pregnancy and breastfeeding require specialist assessment and should be avoided unless the prescriber advises after a risk–benefit review.

Storage

Storage conditions

Proper storage and handling reduce the risk of product degradation and maintain patient safety.

Store Frumil tablets below 25°C and protect from moisture and direct light.

Alternatives and switching

When other combinations may be chosen

Several alternative potassium-sparing diuretic combinations exist and choice depends on clinical goals and formulary constraints.

Alternatives include Moduretic (amiloride with hydrochlorothiazide).

Combinations with spironolactone such as Aldactazide have different pharmacology and potassium effects and may be preferred in certain clinical scenarios.

When switching from one diuretic to another, current bloods, recent BP readings and symptom review should be checked before changing therapy.

Any switch should be recorded clearly on the medication record, with follow-up blood tests arranged after the change.

Overdose, missed dose, adverse reporting and emergency steps

What to do

An overdose may cause severe dehydration, profound low blood pressure and dangerous electrolyte disturbances requiring urgent care.

Immediate action for suspected overdose is to seek emergency medical attention; hospitals will manage with rehydration, electrolyte correction and monitoring.

For a missed dose patients should take the dose when remembered unless it is close to the next dose and they should never double up.

For urgent advice out of hours, contact NHS 111 (or 999 in an emergency).

Delivery across the United Kingdom

Frequently asked questions

Will this tablet make me need the toilet constantly at night?

Taking co-amilofruse in the morning reduces the chance of nocturia; patients often notice increased daytime urination early on but can plan dosing around daily routines.

Do I need blood tests while taking Frumil?

Yes — baseline renal function and electrolytes are recommended, with repeat tests within one to two weeks of starting or after dose changes and periodic monitoring thereafter.

Can I drive while taking Frumil?

If you experience dizziness or fainting you must avoid driving until symptoms settle and you have been assessed by a clinician.

What should I do if I feel muscle weakness?

Muscle weakness can signal an electrolyte issue; stop the medicine only if advised and seek medical advice promptly so blood tests can be arranged.

How should I store the tablets?

Keep below 25°C in the original blister or pharmacy container and protect from moisture and light; the patient information leaflet contains full storage instructions.

Who should I contact if I have side effects?

Report suspected side effects to the national Yellow Card scheme and seek medical attention for severe symptoms such as collapse, severe breathlessness or confusion.