Adco-Retic combines two diuretics in one tablet: hydrochlorothiazide 50 mg and amiloride 5 mg. It is used for high blood pressure and for fluid retention. The amiloride is included to protect potassium, which the hydrochlorothiazide would otherwise deplete — so the two work together rather than simply adding up.
What is Adco Retic?
Adco-Retic is registered in South Africa as Schedule 3:
| Product | Contains |
|---|---|
| Adco-Retic 50 mg/5 mg | Hydrochlorothiazide 50 mg + amiloride hydrochloride 5 mg |
This pairing is common enough to have its own name — co-amilozide — and appears in South Africa under other brands including Amiloretic and Sandoz Co-Amilozide. Being dispensed one rather than another is ordinary generic substitution.
The two ingredients act on different parts of the kidney, and understanding why they are combined explains most of what matters about this tablet.
- Hydrochlorothiazide is a thiazide diuretic. It blocks sodium reabsorption in the distal tubule, so more sodium and water leave in the urine. It does the main work of lowering blood pressure. Its drawback is that it causes potassium loss, because more sodium arriving further down the kidney is exchanged for potassium.
- Amiloride is a potassium-sparing diuretic. It blocks the sodium channel where that exchange happens. On its own it is a weak diuretic — its real value here is that it stops the potassium loss the thiazide would otherwise cause.
So the amiloride is not there to make the tablet stronger. It is there to make it safer, by preventing low potassium — a problem that can cause muscle weakness, cramps and dangerous heart rhythm disturbances, and which is often silent until it is significant.
That protection creates the opposite risk. Because amiloride retains potassium, this tablet can push potassium too high in the wrong circumstances — which is why the cautions below focus heavily on potassium.
What is Adco Retic commonly used for?
- High blood pressure (hypertension), particularly where potassium loss on a thiazide alone is a concern.
- Oedema (fluid retention) from heart failure, liver disease or kidney conditions.
- Heart failure, to reduce fluid overload and breathlessness.
- Situations where potassium needs protecting, such as in people also taking digoxin, where low potassium is especially risky.
High blood pressure has no symptoms in almost everyone who has it. You will probably feel no different on Adco-Retic, and feeling well is not a reason to stop. It is treating a risk of stroke, heart attack, kidney damage and heart failure.
You will pass more urine in the first days or weeks. That settles, while the blood pressure benefit continues — over months, thiazides work mainly by relaxing blood vessels rather than by removing fluid.
How Adco Retic fits into this medicine category
| Group | Examples | What it does |
|---|---|---|
| Thiazide diuretics | Hydrochlorothiazide (Ridaq) | Blood pressure, mild fluid retention |
| Potassium-sparing diuretics | Amiloride, spironolactone | Weak alone; protect potassium |
| Combined thiazide + potassium-sparing | Adco-Retic, Amiloretic | Blood pressure with potassium protection |
| Loop diuretics | Furosemide | Stronger and faster; significant oedema |
| ACE inhibitors | Enalapril, lisinopril | Relax vessels; also raise potassium |
| Calcium channel blockers | Amlodipine | Relax and widen blood vessels |
Note that ACE inhibitors and ARBs also raise potassium. Combining them with a potassium-sparing diuretic is done deliberately at times, but needs monitoring — it is one of the more common causes of dangerously high potassium. See the blood pressure, heart and circulation medicines hub.
What to check before using Adco Retic
Do not take potassium supplements or potassium-containing salt substitutes unless your doctor has specifically told you to. This is the most important practical point. “Low-sodium” or “heart-healthy” salt substitutes are usually potassium chloride, and combined with amiloride they can raise potassium to dangerous levels. Check the label of any salt substitute.
Expect blood tests. Potassium, sodium and kidney function are checked before starting and periodically afterwards. With this combination that monitoring genuinely matters, because potassium can move in either direction.
Take it in the morning, so increased urination does not disturb your sleep.
Tell your doctor or pharmacist if you:
- Have kidney disease. Impaired kidneys plus a potassium-sparing diuretic is the classic setting for dangerously high potassium.
- Have diabetes, where kidney function and potassium handling can both be affected.
- Have gout, or raised uric acid — thiazides can trigger an attack.
- Have liver disease.
- Have Addison’s disease or any condition causing high potassium.
- Have lupus, which thiazides can aggravate.
- Have a sulfonamide allergy.
- Are pregnant or breastfeeding.
- Are elderly, where low sodium, dehydration and falls are more likely.
- Take an ACE inhibitor, ARB, spironolactone, potassium supplements, or trimethoprim — all raise potassium.
- Take lithium, whose levels rise dangerously with thiazides.
- Take digoxin.
- Take anti-inflammatories such as ibuprofen, which raise blood pressure, blunt diuretics and can harm the kidneys in this combination.
If you become unwell with vomiting, diarrhoea or fever, or in very hot weather, ask whether to pause it. Dehydration on a diuretic can affect the kidneys quickly.
Possible cautions and when to ask a pharmacist or doctor
Common effects are passing more urine early on, dizziness when standing, tiredness, muscle cramps, headache and sensitivity to sunlight.
Seek medical advice promptly if you develop:
- Muscle weakness, numbness or tingling, palpitations, or an irregular or slow heartbeat — these can indicate potassium that is too high or too low. High potassium is a medical emergency and often causes few symptoms until the heart is affected.
- Confusion, marked drowsiness, headache, nausea or a seizure — possible low sodium.
- A painful, hot, swollen joint, often the big toe — a gout attack.
- Marked thirst, frequent urination and blurred vision — possible raised blood sugar.
- Severe dizziness or fainting.
- Much less urine than usual.
- Unusual or severe sunburn, or a rash on sun-exposed skin.
- A rash, blistering or peeling skin.
- Persistent vomiting or diarrhoea.
Use sun protection. Photosensitivity is a real effect of the thiazide component.
Stand up slowly, particularly at first, and take care with alcohol.
Tell your doctor if you become pregnant, and check before starting any new medicine — particularly over-the-counter anti-inflammatories and anything containing potassium.
Related medicine guides
- Browse Blood Pressure, Heart & Circulation Medicines guides
- Read: Ciplavasc used for
- Read: Ridaq used for
Frequently asked questions
What are Adco-Retic tablets used for? High blood pressure and fluid retention. Each tablet contains hydrochlorothiazide 50 mg with amiloride 5 mg.
Why does it contain two medicines? Hydrochlorothiazide does the main work but causes potassium loss. Amiloride is added to prevent that, not to make the tablet stronger.
Is it a water tablet? Yes. It is a combination diuretic, increasing the salt and water the kidneys excrete.
When should I take it? In the morning, so increased urination does not disturb your sleep.
Can I use salt substitutes? Not without asking. Most are potassium chloride, and with amiloride they can raise potassium dangerously.
Do I need potassium supplements? Usually not — the amiloride is there to protect potassium. Do not take supplements unless specifically told to.
Why do I need blood tests? To check potassium, sodium and kidney function. Potassium can go too high or too low on this combination, often without symptoms.
Can I stop if my blood pressure is normal? No. Normal readings usually mean it is working. Speak to your doctor before changing anything.