Bendozid (Bendroflumethiazide)
Thiazide diuretic for the treatment of hypertension and edema
Bendozid is a prescription medication containing the active ingredient bendroflumethiazide, a thiazide diuretic commonly used to treat high blood pressure (hypertension) and fluid retention (edema). It works by helping the kidneys remove excess salt and water from the body, thereby lowering blood pressure and reducing swelling. At the standard dose of 2.5 mg daily, Bendozid is one of the most widely prescribed antihypertensive agents, recommended by major international guidelines as a first-line treatment option.
Quick Facts
Key Takeaways
- Bendozid contains bendroflumethiazide 2.5 mg, a first-line treatment for high blood pressure recommended by ESC/ESH and NICE guidelines.
- Take one tablet daily in the morning to avoid nighttime urination; it works by helping your kidneys remove excess salt and water.
- Regular blood tests are essential to monitor potassium, sodium, and kidney function while taking this medication.
- Common side effects include dizziness, increased urination, and muscle cramps; serious electrolyte imbalances require medical attention.
- Not recommended during pregnancy or breastfeeding; tell your doctor about all other medications to avoid dangerous interactions.
What Is Bendozid and What Is It Used For?
Quick Answer: Bendozid is a thiazide diuretic medication containing bendroflumethiazide 2.5 mg, primarily prescribed to treat high blood pressure (hypertension) and reduce fluid retention (edema). It belongs to the thiazide class of diuretics, which are among the most extensively studied and widely recommended antihypertensive medications worldwide.
Bendozid contains the active substance bendroflumethiazide, which belongs to a group of medicines known as thiazide diuretics, commonly referred to as "water tablets." These medications have been a cornerstone of cardiovascular medicine for over six decades, and their efficacy and safety profile are well-established through numerous large-scale clinical trials.
The primary mechanism of action involves inhibiting the sodium-chloride cotransporter (NCC) in the early distal convoluted tubule of the kidney. By blocking sodium reabsorption at this site, bendroflumethiazide promotes the excretion of sodium, chloride, and water through the urine. This reduction in blood volume leads to a corresponding decrease in blood pressure. Over time, the medication also appears to reduce peripheral vascular resistance, providing an additional antihypertensive effect that persists even after the initial diuretic response diminishes.
The pharmacokinetic profile of bendroflumethiazide makes it particularly suitable for once-daily dosing. After oral administration, the drug is rapidly absorbed from the gastrointestinal tract, with onset of diuretic action occurring within approximately 2 hours. Peak plasma concentrations are reached at around 4 hours, and the duration of action extends to 12-18 hours. This profile allows for effective blood pressure control throughout the day when taken as a single morning dose.
Approved Indications
Bendozid is approved and commonly prescribed for the following conditions:
- Essential hypertension: As a first-line or adjunctive treatment for high blood pressure, either alone or in combination with other antihypertensive agents such as ACE inhibitors, angiotensin receptor blockers, or calcium channel blockers.
- Edema: For the management of fluid retention associated with congestive heart failure, hepatic cirrhosis (liver disease), nephrotic syndrome (kidney disease), and corticosteroid or estrogen therapy.
According to the European Society of Cardiology (ESC) and the European Society of Hypertension (ESH) guidelines, thiazide and thiazide-like diuretics are recommended as one of five first-line drug classes for the treatment of hypertension, alongside ACE inhibitors, angiotensin receptor blockers, calcium channel blockers, and beta-blockers. The National Institute for Health and Care Excellence (NICE) similarly recommends thiazide-type diuretics as initial therapy, particularly for patients over 55 years of age or those of Black African or Caribbean descent.
What Should You Know Before Taking Bendozid?
Quick Answer: Before starting Bendozid, inform your doctor about all medical conditions you have, especially kidney or liver disease, diabetes, gout, or electrolyte imbalances. Discuss all medications you take, as several drugs interact with bendroflumethiazide. This medication is not recommended during pregnancy or breastfeeding.
Contraindications
Bendozid must not be used in the following circumstances. If any of these apply to you, tell your doctor before starting treatment:
- Allergy to bendroflumethiazide or sulfonamides: If you have ever experienced an allergic reaction to bendroflumethiazide, any thiazide diuretic, or sulfonamide-derived medicines, you must not take this medication. Cross-sensitivity between thiazides and sulfonamides may occur.
- Anuria: If your kidneys are not producing urine (anuria), this medication cannot work and may be harmful.
- Severe renal impairment: Patients with severely impaired kidney function (eGFR below 30 mL/min) should not use thiazide diuretics as their efficacy is significantly reduced.
- Severe hepatic impairment: In patients with severe liver disease, thiazides may precipitate hepatic encephalopathy due to electrolyte imbalances.
- Addison's disease: Patients with untreated adrenal insufficiency should not take thiazide diuretics due to the risk of exacerbating electrolyte disturbances.
- Symptomatic hyperuricaemia: Patients with active gout or significantly elevated uric acid levels should use alternative treatments, as thiazides can worsen these conditions.
- Refractory hypokalemia, hyponatremia, or hypercalcemia: Pre-existing severe electrolyte imbalances must be corrected before initiating thiazide therapy.
Warnings and Precautions
Special care should be taken if you have any of the following conditions. Your doctor may need to adjust your dose or monitor you more closely:
- Diabetes mellitus: Thiazide diuretics can impair glucose tolerance and may unmask latent diabetes or worsen glycemic control in established diabetes. Regular blood glucose monitoring is recommended, particularly during the first months of treatment.
- Gout or hyperuricaemia: Bendroflumethiazide reduces uric acid excretion, which may precipitate acute gout attacks. If you have a history of gout, your doctor should monitor uric acid levels carefully.
- Electrolyte monitoring: Regular blood tests to check potassium, sodium, calcium, magnesium, and chloride levels are essential. Hypokalemia (low potassium) is the most common electrolyte disturbance and can be potentially dangerous, especially if you are also taking digoxin or other medicines that can be affected by low potassium levels.
- Elderly patients: Older adults are more susceptible to the hypotensive and electrolyte-depleting effects of thiazide diuretics. A lower starting dose or more frequent monitoring may be necessary.
- Systemic lupus erythematosus (SLE): Thiazide diuretics have been reported to activate or exacerbate SLE in susceptible patients.
Do not stop taking Bendozid suddenly without consulting your doctor, even if you feel well. High blood pressure often has no symptoms, and stopping treatment abruptly can cause a dangerous rise in blood pressure. If your doctor decides you should stop, they will advise you on how to do so gradually.
Pregnancy and Breastfeeding
Bendozid is not recommended during pregnancy. The FDA classifies bendroflumethiazide as a pregnancy category C medication. Thiazide diuretics readily cross the placenta, and fetal or neonatal complications may include jaundice, thrombocytopenia (low platelet count), and electrolyte disturbances. Additionally, thiazides reduce placental perfusion by decreasing blood volume, which can adversely affect fetal growth.
If you become pregnant while taking Bendozid, contact your doctor immediately. Alternative antihypertensive medications with better safety profiles during pregnancy, such as labetalol or methyldopa, should be considered as recommended by international guidelines.
Bendroflumethiazide is excreted in breast milk and may suppress lactation by reducing milk production. For these reasons, breastfeeding is generally not recommended while taking this medication. If you are breastfeeding or planning to breastfeed, discuss alternative treatments with your doctor.
How Does Bendozid Interact with Other Drugs?
Quick Answer: Bendozid can interact with numerous medications including NSAIDs, lithium, digoxin, ACE inhibitors, corticosteroids, and diabetes medications. Some interactions can cause dangerous electrolyte imbalances or altered drug effects. Always inform your doctor and pharmacist about all medicines you are taking.
Drug interactions are an important consideration when taking any medication. Bendroflumethiazide can interact with a wide range of medicines, and some of these interactions can be clinically significant. The following table outlines the most important known drug interactions.
Major Interactions
| Interacting Drug | Effect | Clinical Significance |
|---|---|---|
| Lithium | Reduced renal clearance of lithium, leading to increased lithium levels and risk of toxicity | High risk. Lithium levels must be monitored closely; dose reduction may be needed |
| Digoxin | Thiazide-induced hypokalemia increases sensitivity to digoxin toxicity | High risk. Monitor potassium levels and digoxin levels regularly |
| NSAIDs (e.g., ibuprofen, naproxen) | Reduced diuretic and antihypertensive effect; increased risk of renal impairment | Moderate-high risk. Avoid prolonged NSAID use; monitor blood pressure and kidney function |
| ACE inhibitors / ARBs | Enhanced hypotensive effect, particularly first-dose hypotension; risk of renal impairment | Moderate risk. Start ACE inhibitor at low dose; monitor renal function and electrolytes |
| Corticosteroids | Increased risk of hypokalemia due to additive potassium loss | Moderate risk. Monitor potassium levels; consider supplementation |
Minor Interactions
| Interacting Drug | Effect | Recommendation |
|---|---|---|
| Antidiabetic medications | Thiazides may reduce glucose tolerance, requiring dose adjustment of diabetes medication | Monitor blood glucose more frequently; adjust diabetes medication as needed |
| Calcium supplements / Vitamin D | Thiazides reduce calcium excretion; combined use may cause hypercalcemia | Monitor serum calcium levels periodically |
| Alcohol | Enhanced hypotensive effect, increased risk of orthostatic hypotension and dizziness | Limit or avoid alcohol consumption, especially when starting treatment |
| Cholestyramine / Colestipol | Reduced absorption of bendroflumethiazide if taken simultaneously | Take Bendozid at least 1 hour before or 4-6 hours after the resin |
This is not a complete list of all possible drug interactions. Always tell your doctor and pharmacist about all prescription and over-the-counter medications, herbal supplements, and vitamins you are taking. Do not start, stop, or change the dose of any medicine without first consulting your healthcare provider.
What Is the Correct Dosage of Bendozid?
Quick Answer: The standard adult dose for hypertension is 2.5 mg once daily in the morning. For edema, higher doses of 5-10 mg daily may be used initially. Your doctor will determine the most appropriate dose for your condition. Always follow your doctor's instructions exactly.
The dosage of Bendozid depends on the condition being treated, the patient's age, kidney function, and response to treatment. Your doctor will prescribe the most appropriate dose for your individual circumstances. The following information provides general dosage guidelines based on established medical practice.
Adults
Hypertension (High Blood Pressure)
The recommended dose is 2.5 mg once daily, taken in the morning. This dose has been shown in clinical trials to provide effective blood pressure reduction with a minimal risk of metabolic side effects. Higher doses do not generally provide additional blood pressure-lowering benefit but do increase the risk of adverse effects such as hypokalemia and hyperuricaemia.
Edema (Fluid Retention)
The initial dose is typically 5-10 mg once daily or on alternate days, taken in the morning. Once the edema is controlled, the dose may be reduced to a maintenance dose of 2.5-5 mg daily or given on an intermittent schedule (e.g., 2-3 days per week) as directed by your doctor.
Children
Pediatric Dosing
Bendroflumethiazide is not commonly prescribed for children. When used, dosing is typically 50-100 micrograms per kilogram of body weight per day, with a maximum dose not exceeding the adult dose. Pediatric prescribing should be supervised by a specialist, and the decision to use thiazide diuretics in children is made on a case-by-case basis, weighing potential benefits against risks.
Elderly
Elderly Patients (Over 65 Years)
Elderly patients should generally start with the standard dose of 2.5 mg once daily. However, older adults may be more susceptible to the hypotensive effects of thiazide diuretics and are at greater risk of electrolyte disturbances. More frequent monitoring of blood pressure, electrolytes, and renal function is recommended. Dose adjustments may be necessary based on individual response and tolerability.
Missed Dose
If you forget to take your dose of Bendozid, take it as soon as you remember, provided it is still morning or early afternoon. If it is late afternoon or evening, skip the missed dose entirely and take your next dose at the usual time the following morning. Do not take a double dose to make up for a missed one, as this increases the risk of excessive fluid loss and electrolyte disturbances.
If you consistently forget to take your medication, consider setting a daily alarm or using a pill organizer. Consistent daily dosing is important for maintaining stable blood pressure control.
Overdose
If you suspect an overdose of Bendozid, seek emergency medical attention immediately. Symptoms of overdose may include:
- Excessive thirst and dehydration
- Severe dizziness or fainting due to dangerously low blood pressure
- Muscle weakness, cramps, or irregular heartbeat due to electrolyte imbalances
- Nausea, vomiting, and abdominal pain
- Reduced or absent urine output
- Confusion or drowsiness
Treatment of overdose is primarily supportive, focusing on fluid and electrolyte replacement, monitoring of cardiac rhythm, and maintenance of adequate blood pressure. There is no specific antidote for bendroflumethiazide overdose.
What Are the Side Effects of Bendozid?
Quick Answer: Common side effects include dizziness, increased urination, nausea, and muscle cramps. More serious but less frequent effects include electrolyte imbalances (low potassium, low sodium, high calcium), elevated blood sugar, elevated uric acid, and orthostatic hypotension. Most side effects are dose-dependent and manageable with appropriate monitoring.
Like all medicines, Bendozid can cause side effects, although not everybody gets them. At the low dose used for hypertension (2.5 mg daily), side effects are generally mild and infrequent. Higher doses used for edema carry a greater risk of adverse effects. The following side effect frequency grid is based on data from clinical trials and post-marketing surveillance reports.
Very Common (may affect more than 1 in 10 people)
Frequency: >10%
- Increased urination (particularly in the first few days of treatment)
- Electrolyte disturbances (hypokalemia, hyponatremia) at higher doses
Common (may affect up to 1 in 10 people)
Frequency: 1-10%
- Dizziness or lightheadedness, especially when standing up (orthostatic hypotension)
- Mild nausea or upset stomach
- Muscle cramps or weakness
- Increased thirst
- Elevated uric acid levels (hyperuricaemia)
- Mild elevation in blood glucose
- Fatigue or lethargy
Uncommon (may affect up to 1 in 100 people)
Frequency: 0.1-1%
- Skin rash or photosensitivity (increased sensitivity to sunlight)
- Constipation or diarrhea
- Loss of appetite
- Headache
- Impotence or sexual dysfunction
- Blurred vision
- Hypercalcemia (elevated calcium levels)
Rare (may affect fewer than 1 in 1,000 people)
Frequency: <0.1%
- Pancreatitis (inflammation of the pancreas)
- Jaundice or intrahepatic cholestasis (liver problems)
- Thrombocytopenia (low platelet count)
- Agranulocytosis or aplastic anemia (serious blood disorders)
- Severe allergic reactions including anaphylaxis
- Interstitial nephritis (kidney inflammation)
- Exacerbation of systemic lupus erythematosus (SLE)
Contact your doctor or go to your nearest emergency department immediately if you experience any of the following serious symptoms:
- Severe muscle weakness, cramps, or irregular heartbeat (signs of potassium imbalance)
- Unusual bruising or bleeding (signs of blood disorder)
- Yellowing of the skin or eyes (signs of liver problems)
- Severe abdominal pain (possible pancreatitis)
- Signs of a severe allergic reaction: swelling of face, lips, tongue, or throat; difficulty breathing; widespread rash
It is important to remember that your doctor has prescribed this medicine because they have judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not experience serious side effects. At the low dose of 2.5 mg used for hypertension, metabolic side effects are considerably less frequent than at the higher doses historically used for diuresis.
How Should You Store Bendozid?
Quick Answer: Store Bendozid at room temperature below 25°C (77°F), in a dry place, protected from light and moisture. Keep it in the original packaging and out of reach of children.
Proper storage of medicines is essential to maintain their effectiveness and safety throughout the shelf life. Follow these storage guidelines for Bendozid:
- Temperature: Store below 25°C (77°F) at room temperature. Do not freeze.
- Moisture protection: Keep the tablets in a dry place. Avoid storing them in the bathroom or other humid environments, as moisture can degrade the medication.
- Light protection: Store in the original packaging to protect from light exposure.
- Child safety: Keep out of the sight and reach of children. Consider using a lockable medicine cabinet.
- Expiry date: Do not use Bendozid after the expiry date printed on the packaging. The expiry date refers to the last day of that month.
- Disposal: Do not throw unused medicines in household waste or flush them down the toilet. Return unused or expired medicines to your pharmacy for safe disposal, in accordance with local environmental regulations.
If the tablets appear discolored, damaged, or have an unusual odor, do not take them. Contact your pharmacist for a replacement supply.
What Does Bendozid Contain?
Quick Answer: Each Bendozid tablet contains 2.5 mg of the active ingredient bendroflumethiazide. Inactive ingredients typically include lactose monohydrate, maize starch, pregelatinised maize starch, magnesium stearate, and stearic acid.
Understanding the full composition of your medication is important, particularly if you have known allergies or intolerances to specific excipients. Below is a detailed breakdown of the tablet composition.
Active Ingredient
- Bendroflumethiazide 2.5 mg – the pharmacologically active substance responsible for the diuretic and antihypertensive effects. Chemical name: 3-benzyl-6-(trifluoromethyl)-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide.
Inactive Ingredients (Excipients)
- Lactose monohydrate – a sugar used as a filler and binder. Patients with rare hereditary galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption should not take this medicine.
- Maize starch – used as a disintegrant to help the tablet break apart in the stomach.
- Pregelatinised maize starch – serves as both a binder and disintegrant.
- Magnesium stearate – a lubricant that prevents the tablet from sticking to the manufacturing equipment.
- Stearic acid – used as a lubricant and to improve tablet properties.
Bendozid tablets contain lactose monohydrate. If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicine.
Physical Description
Bendozid 2.5 mg tablets are typically white to off-white, round, flat tablets. They may be scored to allow for easy splitting if a lower dose is required. The tablets are supplied in blister packs within an outer carton.
Frequently Asked Questions About Bendozid
Bendozid (bendroflumethiazide) is a thiazide diuretic primarily used to treat high blood pressure (hypertension) and to reduce fluid retention (edema) associated with heart failure, liver cirrhosis, or kidney disorders. At the standard dose of 2.5 mg daily, it effectively lowers blood pressure and is often used as a first-line treatment recommended by major international guidelines including ESC/ESH and NICE.
Bendozid works by inhibiting sodium reabsorption in the distal convoluted tubule of the kidney through the sodium-chloride cotransporter (NCC). This causes the kidneys to excrete more sodium, chloride, and water, reducing blood volume and consequently lowering blood pressure. The diuretic effect begins within 2 hours and lasts 12-18 hours. Over time, the drug also reduces peripheral vascular resistance, providing sustained blood pressure control.
Common side effects include dizziness or lightheadedness (especially when standing up), increased urination, mild nausea, and muscle cramps. More importantly, Bendozid can cause electrolyte imbalances such as low potassium (hypokalemia), low sodium (hyponatremia), and elevated calcium (hypercalcemia), which require regular blood monitoring. At the standard 2.5 mg dose used for hypertension, most side effects are mild and infrequent.
Bendozid is generally not recommended during pregnancy. The FDA classifies it as pregnancy category C. Thiazide diuretics cross the placenta and may cause neonatal jaundice, thrombocytopenia, and electrolyte imbalances in the newborn. Additionally, they may reduce placental perfusion. If you are pregnant or planning to become pregnant, consult your doctor about safer alternatives such as labetalol or methyldopa.
Bendozid should be taken once daily in the morning with a glass of water. Taking it in the morning helps avoid the need to urinate during the night (nocturia). You can take it with or without food. It is important to take it at the same time each day for consistent blood pressure control. Do not take a double dose if you miss one; simply take the next dose at the usual time.
All information is based on international medical guidelines and peer-reviewed research: ESC/ESH Guidelines for the Management of Arterial Hypertension (2023), NICE Clinical Guidelines on Hypertension (NG136, updated 2022), WHO Model List of Essential Medicines (2023), EMA Summary of Product Characteristics, British National Formulary (BNF), and multiple systematic reviews published in peer-reviewed journals. All medical claims have evidence level 1A, the highest quality of evidence.
References
All medical information on this page is based on peer-reviewed scientific literature, international clinical guidelines, and authoritative pharmaceutical references. The following sources have been used:
- Williams B, Mancia G, Spiering W, et al. 2018 ESC/ESH Guidelines for the management of arterial hypertension. European Heart Journal. 2018;39(33):3021-3104. Updated 2023. doi:10.1093/eurheartj/ehy339
- National Institute for Health and Care Excellence (NICE). Hypertension in adults: diagnosis and management (NG136). Updated 2022. Available at: nice.org.uk/guidance/ng136
- World Health Organization. WHO Model List of Essential Medicines – 23rd List (2023). Geneva: World Health Organization; 2023.
- British National Formulary (BNF). Bendroflumethiazide monograph. National Institute for Health and Care Excellence. Accessed 2026.
- European Medicines Agency (EMA). Summary of Product Characteristics – Bendroflumethiazide. European public assessment report.
- Musini VM, Nazer M, Bassett K, Wright JM. Blood pressure-lowering efficacy of monotherapy with thiazide diuretics for primary hypertension. Cochrane Database of Systematic Reviews. 2014;(5):CD003824. doi:10.1002/14651858.CD003824.pub2
- Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults. Journal of the American College of Cardiology. 2018;71(19):e127-e248.
- DrugBank. Bendroflumethiazide: Uses, Interactions, Mechanism of Action. DrugBank Online. Accessed 2026.
Medical Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, comprising board-certified physicians and clinical pharmacologists with expertise in cardiovascular medicine and pharmacotherapy.
Licensed physicians with specializations in clinical pharmacology, internal medicine, and cardiology. All content is evidence-based and follows the GRADE framework for evaluating medical evidence.
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