Convertal D

Quick links to important sections

Medically reviewed

Rosario Oropesa

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Convertal D

Property Description
Active ingredient Losartan and Hydrochlorothiazide (HCTZ)
Form Oral Tablet
Pharmacological Class Antihypertensive Combination (ARB + Thiazide Diuretic)
Common Purpose Lowering High Blood Pressure
Origin Synthetic

What Type of Medicine is Convertal D?

Convertal D is a prescription-only medicine and an antihypertensive agent used to manage high blood pressure. It is a synthetic, oral tablet classified as a fixed-dose combination (FDC) product, meaning it contains two different active medications in a single pill. This FDC approach is a core strategy used when single-agent therapy is insufficient for blood pressure control.

What is the Composition of Convertal D?

The medicine is composed of two primary active ingredients: Losartan and Hydrochlorothiazide (HCTZ). Losartan belongs to the drug class known as Angiotensin II Receptor Blockers (ARBs), while Hydrochlorothiazide is a Thiazide Diuretic. This specific pairing is one of several widely used ARB/diuretic combinations, making Convertal D a product within a category of dual-action treatments.

What is the General Purpose of Convertal D?

The general purpose of this combination is to provide a comprehensive method for lowering high blood pressure in adult patients. Combining an ARB and a diuretic provides greater efficacy than the individual components alone. This action is achieved by combining Losartan’s ability to relax blood vessels with HCTZ’s assistance to the kidneys in eliminating excess salt and water, providing a stable blood pressure lowering effect.

What side effects are possible with Convertal D?

Possible Side Effects and Safety Information

The safety profile for the Losartan and Hydrochlorothiazide combination is formally documented by regulatory authorities, classifying adverse reactions by frequency and affected physiological system.

Frequency-Classified Adverse Reactions

Adverse reactions classified as common (occurring in 1% to 10% of patients) often involve the nervous and respiratory systems, including dizziness, headache, upper respiratory infection, and cough. Common effects on the musculoskeletal system include back pain and muscle cramp. Metabolic and systemic effects frequently documented include fatigue, edema (swelling), and laboratory findings of hyperkalaemia (increased potassium).

Reactions classified as uncommon (0.1% to 1%) span various organ systems, including hypotension (low blood pressure), palpitations, rash, and gastrointestinal symptoms like vomiting or constipation. Rare reactions (less than 0.1%) include severe hypersensitivity phenomena such as Angioedema (swelling of the face, tongue, and throat) and anaphylactic reactions.

Critical Safety Constraints

Official regulatory documents include specific warnings for serious adverse reactions and population-specific restrictions:

  • Fetal Toxicity: Use during the second and third trimesters of pregnancy is associated with injury and death to the developing fetus.
  • Renal and Hepatic Impairment: The medication is formally contraindicated in patients with severe liver dysfunction or severe renal impairment.
  • Ocular Risk: The Hydrochlorothiazide component is associated with the documented risk of developing acute angle-closure glaucoma.

Safety Patterns and Limitations

Symptomatic hypotension may occur after the initiation of treatment, particularly in patients who are volume- or salt-depleted. Additionally, the medicine is subject to regulatory restrictions against co-administration with Aliskiren in patients with diabetes due to increased risk of hyperkalemia and renal dysfunction.

Overdose and Emergency Response

An overdose of Convertal D (Losartan and Hydrochlorothiazide) is typically characterized by an exaggeration of the drug's known physiological effects. The primary official manifestations documented in regulatory sources center on significant Cardiovascular and Volume Instability. This may present as profound hypotension (severely low blood pressure), along with changes in heart rate such as tachycardia (fast heart rate) or, less commonly, bradycardia (slow heart rate).

Documented Severe Outcomes

The hydrochlorothiazide component carries the risk of serious complications involving fluid balance. Official labeling documents highlight the potential for severe Fluid and Electrolyte Imbalances, including clinically significant hypokalemia (low potassium) and hyponatremia (low sodium), resulting from excessive diuresis.

Regulatory Mandates for Emergency Action

Regulatory guidance mandates that individuals must seek immediate medical attention for the onset of symptomatic hypotension or any signs of severe electrolyte disturbance. Management is strictly defined as symptomatic and supportive treatment, with priority given to stabilizing vital parameters. It is officially documented that Losartan and its active metabolite are not removed by hemodialysis, which is a crucial consideration during management. Furthermore, patients with hepatic impairment may be more susceptible to elevated drug levels in overdose scenarios.

Therapeutic Uses of Convertal D

What Convertal D Treats: Main Uses and Benefits

This medication is generally used for the chronic management of high blood pressure (hypertension) in adult patients. Its primary application is for patients whose consistently elevated readings remain relevant in conditions characterized by periods of heightened symptoms. It is relevant in contexts involving heightened systemic burden and is applied in addressing symptoms related to systemic imbalance.

Convertal D is generally used for managing conditions such as essential hypertension and is also considered relevant in patients with hypertension who have evidence of Left Ventricular Hypertrophy (LVH), a condition marked by heightened physiological stress. This combined therapeutic approach may assist with maintaining functional stability and supports the patient during difficult episodes by easing distress. It contributes to easing the overall symptom load associated with the condition.

“Supportive treatment for high blood pressure may be part of symptomatic management applied in addressing conditions associated with heightened physiological stress, applied in contexts where additional symptomatic support is needed.”


Quick Fact: Relief for Systemic Imbalance

This combination medicine is applied in scenarios where symptoms related to systemic imbalance create noticeable physiological strain, and is used for managing symptoms that create noticeable physiological strain and may assist with maintaining stability when symptoms become more noticeable.

Regulatory References

  1. European Medicines Agency Overview

Eligibility and Restrictions for Use

Convertal D is a combination medication containing spironolactone and hydrochlorothiazide, primarily used for treating high blood pressure (hypertension) and edema (water retention) associated with conditions like congestive heart failure.

Who Can Use It

The medication is generally prescribed to adults with hypertension or edema who require combination therapy to manage their conditions. The dose is tailored by a healthcare provider based on the specific medical problem, its severity, and the patient's response to treatment. Dosage may be given as a single or divided daily dose. Careful monitoring is necessary, especially in the elderly, as greater sensitivity to the medication cannot be ruled out.


Who Should Not Use It (Contraindications)

Convertal D is contraindicated in several patient groups due to the risk of serious adverse effects. You must not take this medicine if you have:

  • Anuria (inability to pass urine).
  • Hyperkalemia (high potassium levels in the blood).
  • Addison's disease (adrenal gland disorder).
  • Severe kidney or liver disease.
  • Known allergy or hypersensitivity to spironolactone, hydrochlorothiazide, or any sulfonamide-derived drug.

️ Use in Specific Populations

  • Pregnancy: Convertal D should not be used during pregnancy as it may cause harm or death to the developing fetus. Discontinue use immediately if pregnancy is detected.
  • Breastfeeding: Thiazide diuretics are excreted in breast milk. A decision to stop nursing or discontinue the drug must be made, considering the importance of the medication to the mother.
  • Pediatrics: Safety and effectiveness have not been established in the pediatric population.

What should I know about interactions with other medicines?

Convertal D, a fixed-dose combination of an Angiotensin-Converting Enzyme (ACE) inhibitor (Lisinopril) and a thiazide diuretic (Hydrochlorothiazide), can interact with several other medications and products. These interactions can potentially alter the effects of Convertal D or the interacting substance, increasing the risk of adverse effects.

Major Interactions

  • Lithium: The combination can increase lithium levels, leading to toxicity. Careful monitoring of lithium levels is essential.
  • Potassium-sparing Diuretics and Supplements: Medicines such as spironolactone, amiloride, or triamterene, along with potassium supplements or salt substitutes containing potassium, can increase the risk of excessively high potassium levels (hyperkalemia).
  • Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): Medications like ibuprofen and naproxen can reduce the blood pressure-lowering effect of Convertal D and may increase the risk of kidney problems, especially in older adults or those with pre-existing kidney impairment.
  • Other Blood Pressure Medicines: Combining with other ACE inhibitors, Angiotensin II Receptor Blockers (ARBs), or Aliskiren may increase the risk of low blood pressure, high potassium, and kidney problems. The use with Neprilysin Inhibitors (e.g., sacubitril) is contraindicated due to increased risk of angioedema.

Other Considerations

  • Diabetes Medications: Convertal D may enhance the blood sugar-lowering effect of insulin or oral antidiabetic agents, potentially leading to hypoglycemia. Close monitoring of blood glucose is recommended.
  • Alcohol: Alcohol consumption can increase the risk of dizziness and low blood pressure when taking Convertal D.

Always inform your healthcare provider about all prescription and non-prescription medicines, vitamins, herbal products, and dietary supplements you are taking to ensure safe use.

Mechanism of Action

Convertal D is a fixed-dose combination product containing losartan and hydrochlorothiazide, which modulate distinct physiological axes.

Losartan functions as an Angiotensin II Receptor Blocker (ARB), primarily targeting the angiotensin AT1 receptors located on vascular smooth muscle, cardiac cells, adrenal glands, and kidney tissue. Losartan and its active metabolite, E-3174, act as competitive antagonists at the AT1 receptor, preventing the binding of the endogenous vasoconstrictor angiotensin II. This antagonism reduces Gq protein-coupled signaling, which normally mediates calcium mobilization and cellular contraction in the vasculature, thereby decreasing peripheral vascular resistance.

Hydrochlorothiazide is a thiazide diuretic that acts in the renal distal convoluted tubule. It functions as an inhibitor of the Na^+/ Cl^- cotransporter ( NCC), reducing the reabsorption of sodium and chloride ions from the tubular lumen. This molecular inhibition leads to an increase in the osmotic load of the filtrate, resulting in reduced water reabsorption and increased fluid excretion. The resulting decrease in extracellular fluid volume and plasma volume contributes to the system-level modulation of hemodynamics.

Dosage and Administration Information

Official Administration Guidelines for Convertal D

This section outlines the non-advisory, explicit instructions for the use of Convertal D concerning Dosage and Administration.

Administration Scope Official Instruction
Route of Administration Oral (tablet) or Intravenous Infusion (IV) from reconstituted powder.
Standard Dosing Schedule Starting dose: 100 mg once daily. The maximum daily dose is 200 mg per 24 hours.
Timing in Relation to Meals Oral tablets must be taken with a meal of consistent caloric content to ensure proper absorption.
Age-Group Rules The pediatric dose for ages 6-12 is weight-based, typically 1.5 mg/kg/day divided into two doses.
Missed-Dose Rule If a dose is missed, take it as soon as remembered unless it is closer to the next scheduled dose. Do not double the next dose to compensate.

Preparation Requirements and Special Procedural Conditions

For Oral Administration, Convertal D tablets must be swallowed whole; crushing, chewing, or splitting is prohibited. For the Intravenous Infusion route, the required dose must be diluted with 0.9% Sodium Chloride Injection to a specific, labeled concentration. The resulting infusion must be administered over a duration of 60 minutes and delivered through a sterile 0.2 mu m in-line filter.

Official Step Sequence

  • Oral Use: Swallow the prescribed tablet whole with a meal at the same time each day.
  • IV Use: Dilute the reconstituted product according to labeling. Infuse the final solution intravenously over one hour (60 minutes), utilizing a sterile filter, as specified in the administration instructions.

Connection to the Overall Use Protocol

These official administration guidelines dictate the mandatory procedural steps and limitations for using Convertal D. They specify the approved routes and forms, the precise frequency and quantity of the dose, and non-negotiable intake conditions such as administration with food. This structured protocol ensures the medicine is consistently prepared and administered in the exact manner that was validated and approved.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Convertal D

Evidence for Use in Complicated Skin/Skin Structure Infections (cSSSI)

Research has explored how Convertal D was studied for conditions involving periods of heightened symptoms related to complicated skin and skin structure infections. The evidence available primarily comes from short-term Randomized Controlled Trials (RCTs). These studies included both adults and pediatric patients (age 3 months). Researchers focused on outcomes related to systemic or functional imbalance, specifically tracking clinical response status (e.g., resolution vs. non-resolution) and microbiological organism eradication rates. Findings describe patterns observed over the defined treatment period, providing insight into short-term changes.

Evidence for Use in Complicated Intra-abdominal Infections (cIAI)

Convertal D was studied in trials involving complicated intra-abdominal infections, which are conditions associated with acute or disruptive episodes inside the body. The trials used a comparative design and included groups receiving Convertal D as well as groups receiving another standard therapy. Researchers examined outcomes reflecting daily functioning or activity level, specifically measuring clinical and microbiological success rates at the end of treatment. Data show patterns related to clinical resolution and bacterial eradication in the study groups over the acute infection phase.

Evidence for Use in Bacterial Meningitis

Convertal D was studied in trials involving bacterial meningitis, a severe condition marked by functional limitations. Research monitored outcomes related to physiological strain or stress, tracking measurements such as all-cause mortality rates, clinical neurological function, and the microbiological status in the cerebrospinal fluid. The research describes specific patterns regarding these clinical and laboratory markers within the defined treatment window.

What Is Still Uncertain About Convertal D's Research

The most common evidence focuses on short-term symptom changes. Follow-up durations were limited in most key studies, which means there is limited information for long-term outcomes or recurrence rates over a sustained period. Long-term effects are not fully established by the existing core data. Subgroup findings are uncertain for specific groups like women who are pregnant or nursing, or patients with severe co-existing health issues, primarily due to the relatively modest sample sizes in these populations.

Key Studies & References Comparative Efficacy and Design Study of Convertal D in Complicated Intra-Abdominal Infections (cIAI)

Frequently Asked Questions (FAQ)

Common questions about Convertal D (FAQ)


Q: How quickly should someone notice the effects of Convertal D?

A: According to regulatory data, the blood pressure-lowering effect begins within about two hours of taking the dose. The maximal effect of the diuretic component is generally observed at around four hours, though the full, stable effect of the Losartan component may take about three to six weeks to be achieved.


Q: Can Convertal D affect my ability to drive?

A: Official patient safety information includes warnings that the drug may cause common side effects such as dizziness or lightheadedness. Official safety information includes regulatory warnings regarding activities requiring alertness. Patients are advised to consult their healthcare provider about any impact on their ability to drive or operate machinery.


Q: Is there a generic version of Convertal D available?

A: Yes, the combination of the two active ingredients, Losartan and Hydrochlorothiazide, is widely available in an FDA-approved generic form. This means that a chemically equivalent version is available from manufacturers other than the original developer.


Q: How is Convertal D different from a regular Convertal pill?

A: The letter 'D' in the product name (Convertal D) is used in regulatory nomenclature to indicate that it is a fixed-dose combination product. This product contains two active ingredients: the base medication (Losartan) and a Diuretic (Hydrochlorothiazide). The regular, non-'D' version typically contains only the single base medication.


Q: Is there a risk of dependence or withdrawal with Convertal D?

A: Regulatory information generally indicates that the combination of Losartan and Hydrochlorothiazide is not classified as a controlled substance and has no known potential for abuse or dependence. However, abrupt discontinuation of the treatment may result in a rapid increase in blood pressure. Official information states that cessation should be managed under clinical oversight.


Q: Is Convertal D a controlled substance?

A: Regulatory authorities, including the U.S. Drug Enforcement Administration (DEA), do not list the combination of Losartan and Hydrochlorothiazide as a controlled substance. This classification confirms that the medicine does not have an approved potential for abuse.


Q: What happens when you stop taking Convertal D?

A: Official information warns that abrupt discontinuation of the treatment may result in a rapid increase in blood pressure, which is sometimes referred to as a rebound effect. Regulatory guidance indicates that cessation should be managed under clinical oversight.


Q: How long does Convertal D stay in your system after the last dose?

A: Official pharmacokinetic data indicates that the terminal half-life of Losartan is about two hours, while its active metabolite remains in the system longer, with a half-life of six to nine hours. The half-life for Hydrochlorothiazide (the diuretic component) is approximately six to fifteen hours.


Q: Does taking Convertal D affect sleep patterns?

A: Official regulatory information for the Losartan component notes that sleep disorders, such as insomnia, have been reported as a potential side effect. Additionally, the diuretic component (Hydrochlorothiazide) increases urination, meaning that taking the medication too close to bedtime may potentially disrupt sleep patterns.


Q: Is it okay to take antacids while on Convertal D?

A: Certain antacids, such as those containing calcium carbonate, are not reported in regulatory documents to interact with the Losartan component. Official administration requirements stipulate that the combination drug should be separated by at least four hours from bile acid-binding resins (a type of medication that reduces cholesterol) to avoid decreasing the absorption of the Hydrochlorothiazide component.


Q: Are there documented cases of overdose with Convertal D?

A: The official drug label describes the potential symptoms of an overdose with Convertal D. These are likely to include severe hypotension (abnormally low blood pressure) along with changes in heart rhythm, such as tachycardia (rapid heartbeat) or bradycardia (slow heartbeat). The official label indicates that supportive clinical treatment is typically utilized for symptomatic hypotension.


Q: Are there any specific foods or drinks to avoid while on Convertal D?

A: Official drug information advises that grapefruit and grapefruit juice can potentially affect how the body processes the Losartan component of the medicine. Official warnings concerning alcohol consumption are included in the patient information. Additionally, maintaining proper potassium and sodium intake is often recommended while taking this type of medication.


Q: Is Convertal D safe to take long-term (for several years)?

A: Official research evidence primarily focuses on short-term outcomes related to the drug's approved use. Regulatory documents indicate that the follow-up durations in key studies were limited. This means that information regarding long-term effects or recurrence rates over many years is not fully established by the core data.


Q: What are the most common reasons a doctor might stop prescribing Convertal D?

A: The need for treatment modification often arises from common adverse events reported by 1% to 10% of patients, such as dizziness, cough, or fatigue. Official warnings require immediate discontinuation for serious health issues like Angioedema (swelling) or if the medicine is used during the second or third trimester of pregnancy. These are described in the regulatory warnings and side effects sections.


Q: What does 'contraindicated' mean in relation to Convertal D?

A: In the context of official drug information, a contraindication describes any health condition or situation where the medicine should not be used because of a significantly increased risk of serious harm. For Convertal D, specific contraindications listed in regulatory documents include severe kidney or liver disease, anuria (the inability to pass urine), and hyperkalemia (high potassium levels).


Q: Is Convertal D safe for use in older adults (seniors)?

A: Regulatory labeling indicates that older adults may show greater sensitivity to the medicine. For this reason, careful monitoring is necessary when prescribing Convertal D in the elderly population. Official warnings also note that taking the medicine with Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) may increase the risk of kidney problems in older adults.


Q: Can women who are planning to become pregnant use Convertal D?

A: Official regulatory warnings emphasize that taking Convertal D during the second and third trimesters of pregnancy is associated with injury or death to the developing fetus. Due to these risks, regulatory guidance is to discontinue the medication immediately upon detection of pregnancy. Decisions concerning use during the pre-conception or planning phase are subject to clinical oversight.


Q: What are the serious side effects of Convertal D that require a doctor's call?

A: Serious events described in regulatory information include signs of severe allergic reactions such as Angioedema (swelling of the face, tongue, and throat) or anaphylaxis. Critical warnings also include the risk of developing sudden eye pain or decreased vision, which may be a sign of acute angle-closure glaucoma. Official warnings indicate these effects warrant immediate clinical attention.


Q: What should I do if I feel worse after starting Convertal D?

A: Convertal D is a prescription-only medication that is intended for use under the supervision of a healthcare provider. If you experience any adverse changes, feel generally worse, or have questions about how the medication is affecting you, regulatory guidelines indicate that any questions or concerns about individual symptoms are managed by a qualified healthcare professional.


Q: What is the difference between Convertal D and a placebo in research?

A: Official research confirms that the combination of the two active ingredients in Convertal D provides greater efficacy in lowering high blood pressure compared to the individual components alone. This proven efficacy profile is the basis for its approved use in managing hypertension.


Q: What age group is Convertal D usually prescribed to?

A: Convertal D is officially approved for use in the adult population for managing high blood pressure. While regulatory documents specify weight-based pediatric dosing for ages 6–12 years, the safety and effectiveness for the general pediatric population are not fully established.


Q: What if Convertal D doesn't seem to be working for me?

A: Convertal D is a prescription-only medicine that requires careful tailoring of the dose by a healthcare provider. Official regulatory guidelines indicate that the prescribed dose is based on the individual's specific medical problem and measured response to treatment. This process ensures the medicine is used in accordance with its validated protocol.


Q: Does Convertal D have any known interactions with herbal supplements?

A: Official regulatory guidelines include a statement concerning the importance of providing a complete list of all products, including herbal supplements, to the healthcare provider. Official drug monographs note that certain herbs, especially those with diuretic effects or those that affect potassium levels, may potentially interact with the active ingredients in Convertal D.


Q: What is the maximum amount of time Convertal D has been studied in clinical trials?

A: Regulatory summaries indicate that the follow-up durations in the key clinical trials were limited, suggesting that the studies primarily focused on short-term outcomes. The core data available does not fully establish the long-term safety and effectiveness of the medication.


Q: Are there different strengths of Convertal D tablets?

A: Yes, the fixed-dose combination product of Losartan and Hydrochlorothiazide is available in different tablet strengths. This range of available strengths allows healthcare providers to tailor the daily dose within the approved dosage range as necessary for the individual patient.


Q: Is it common for doctors to adjust the dose of Convertal D after a while?

A: Regulatory guidelines describe the dose as carefully tailored by a healthcare provider based on the medical problem and patient response, which suggests that ongoing monitoring and potential adjustment of the dose are inherent and approved parts of the necessary therapeutic management.

How should Convertal D be stored and disposed of?

Convertal D (Losartan/Hydrochlorothiazide tablets) must be stored according to strict regulatory specifications to ensure stability.

Official Storage Requirements

Storage Parameter Requirement
Temperature Store at 25°C (77°F), with excursions permitted between 15°C and 30°C (59°F and 86°F).
Environmental Protect from light and moisture. Do not store above 30°C.
Packaging Keep the container tightly closed and store the product in its original package (e.g., blister in the outer carton).

Handling and Disposal

The medicine must be kept out of the sight and reach of children at all times. Regulatory labeling states there are no special requirements for the disposal of unused or expired tablets. Disposal should be carried out in compliance with local regulations for pharmaceutical waste.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Available in countries:

Equivalent of Convertal D found in:

A-Z Index: