Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus. When pregnancy is detected, discontinue therapy as soon as possible.
Hypertension: Oral: Losartan 50 mg/hydrochlorothiazide 12.5 mg or losartan 100 mg/hydrochlorothiazide 12.5 mg or losartan 100 mg/hydrochlorothiazide 25 mg once daily; adjust dose as needed based on blood pressure response. Patients already taking losartan and/or hydrochlorothiazide may be switched to a combination product for individually titrated agents. Maximum dose: Losartan 100 mg/hydrochlorothiazide 25 mg per day.
Hypertension with left ventricular hypertrophy: Oral: Initial: Losartan 50 mg/hydrochlorothiazide 12.5 mg once daily; adjust dose as needed based on blood pressure response. Patients already taking losartan and/or hydrochlorothiazide may be switched to a combination product for individually titrated agents. Maximum dose: Losartan 100 mg/hydrochlorothiazide 25 mg once daily.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
CrCl ≥30 mL/minute: No dosage adjustment necessary.
CrCl <30 mL/minute: Use is not recommended.
Use is not recommended as initial therapy. Should be used with caution in patients with ascites due to cirrhosis (AASLD [Biggins 2021; AASLD [Runyon 2013]).
Refer to adult dosing.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Also see individual agents.
1% to 10%:
Nervous system: Dizziness (6%)
Neuromuscular & skeletal: Back pain (2%)
Respiratory: Upper respiratory tract infection (6%)
Frequency not defined:
Cardiovascular: Chest pain, necrotizing angiitis, orthostatic syncope, palpitations, tachycardia, vasculitis
Dermatologic: Cutaneous lupus erythematosus, pruritus, skin photosensitivity, skin rash, toxic epidermal necrolysis, urticaria
Endocrine & metabolic: Electrolyte disorder (including hypokalemia, hyponatremia), hyperglycemia, hyperuricemia
Gastrointestinal: Abdominal pain, anorexia, dysgeusia, dyspepsia, gastric irritation, nausea, pancreatitis, sialadenitis, stomach cramps, vomiting
Genitourinary: Erectile dysfunction, glycosuria, impotence
Hematologic & oncologic: Agranulocytosis, anemia, aplastic anemia, hemolytic anemia, leukopenia, purpuric disease
Hepatic: Hepatic insufficiency, intrahepatic cholestatic jaundice, jaundice
Hypersensitivity: Hypersensitivity angiitis
Nervous system: Asthenia, headache, insomnia, malaise, migraine, paresthesia, restlessness
Neuromuscular & skeletal: Muscle cramps, muscle spasm
Ophthalmic: Blurred vision (transient), xanthopsia
Renal: Interstitial nephritis, renal failure syndrome, renal insufficiency
Respiratory: Nasal congestion
Postmarketing:
Dermatologic: Erythroderma
Hematologic & oncologic: Henoch-Schönlein purpura, thrombocytopenia
Hypersensitivity: Anaphylaxis, angioedema
Neuromuscular & skeletal: Rhabdomyolysis
Hypersensitivity to losartan, hydrochlorothiazide, sulfonamide-derived drugs, or any component of the formulation; concomitant use with aliskiren in patients with diabetes mellitus; anuria.
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Note: Although the FDA-approved product labeling states this medication is contraindicated in patients with hypersensitivity to sulfonamide-containing drugs, the scientific basis of this cross-sensitivity has been challenged.
Canadian labeling: Additional contraindications (not in U.S. labeling): Concomitant use with aliskiren in patients with moderate-to-severe renal impairment (GFR <60 mL/minute/1.73 m2)
Concerns related to adverse effects:
• Angioedema: Angioedema has been reported rarely with some angiotensin II receptor antagonists (ARBs) and may occur at any time during treatment (especially following first dose). It may involve the head and neck (potentially compromising airway) or the intestine (presenting with abdominal pain). Patients with idiopathic or hereditary angioedema or previous angioedema associated with ACE-inhibitor therapy may be at an increased risk. Prolonged frequent monitoring may be required, especially if tongue, glottis, or larynx are involved, as they are associated with airway obstruction. Patients with a history of airway surgery may have a higher risk of airway obstruction. Discontinue therapy immediately if angioedema occurs. Aggressive early management is critical. Intramuscular (IM) administration of epinephrine may be necessary. Do not readminister to patients who have had angioedema with ARBs.
• Electrolyte disturbances: Hyperkalemia may occur with losartan; risk factors include renal dysfunction, diabetes mellitus, and concomitant use of potassium-sparing diuretics, potassium supplements, and/or potassium-containing salts. Use cautiously, if at all, with these agents and monitor potassium closely. Thiazide diuretics may cause hypokalemia, hypochloremic alkalosis, hypomagnesemia, and hyponatremia.
• Hypersensitivity reactions: Hypersensitivity reactions may occur with hydrochlorothiazide. Risk is increased in patients with a history of allergy or bronchial asthma.
• Hypotension: Symptomatic hypotension may occur upon initiation in patients who are salt- or volume-depleted (eg, those treated with high-dose diuretics); correct volume depletion prior to administration. This transient hypotensive response is not a contraindication to further treatment with losartan/hydrochlorothiazide.
• Ocular effects: Hydrochlorothiazide may cause acute transient myopia and acute angle-closure glaucoma.
• Photosensitivity: Photosensitization may occur with use of hydrochlorothiazide.
• Renal function deterioration: May be associated with deterioration of renal function and/or increases in serum creatinine, particularly in patients with low renal blood flow (eg, renal artery stenosis, heart failure) whose glomerular filtration rate (GFR) is dependent on efferent arteriolar vasoconstriction by angiotensin II; deterioration may result in oliguria, acute renal failure, and progressive azotemia. Small increases in serum creatinine may occur following initiation; consider discontinuation only in patients with progressive and/or significant deterioration in renal function.
• Skin cancer, nonmelanoma: Prolonged use (≥3 years) may increase the risk for squamous cell carcinoma up to 4 times and increase the risk for basal cell carcinoma up to 1.25 times compared to patients not treated with hydrochlorothiazide (Pedersen 2018; Pottegård 2017).
• Sulfonamide (“sulfa”) allergy: The product labeling for many medications containing a sulfonamide chemical group includes a broad contraindication in patients with a prior allergic reaction to sulfonamides. There is a potential for cross-reactivity between members of a specific class (eg, two antibiotic sulfonamides). However, concerns for cross-reactivity have previously extended to all compounds containing the sulfonamide structure (SO2NH2). An expanded understanding of allergic mechanisms indicates cross-reactivity between antibiotic sulfonamides and nonantibiotic sulfonamides may not occur or at the very least this potential is extremely low (Brackett 2004; Johnson 2005; Slatore 2004; Tornero 2004). In particular, mechanisms of cross-reaction due to antibody production (anaphylaxis) are unlikely to occur with nonantibiotic sulfonamides. T-cell-mediated (type IV) reactions (eg, maculopapular rash) are less well understood and it is not possible to completely exclude this potential based on current insights. In cases where prior reactions were severe (Stevens-Johnson syndrome/TEN), some clinicians choose to avoid exposure to these classes.
Disease-related concerns:
• Aortic/mitral stenosis: Use losartan with caution in patients with significant aortic/mitral stenosis.
• Ascites: Generally, avoid use in patients with ascites due to cirrhosis or refractory ascites; if use cannot be avoided in patients with ascites due to cirrhosis, monitor BP and renal function carefully to avoid rapid development of renal failure (AASLD [Runyon 2013]).
• Bariatric surgery: Dehydration: Avoid diuretics in the immediate postoperative period after bariatric surgery; electrolyte disturbances and dehydration may occur. Diuretics may be resumed, if indicated, once oral fluid intake goals are met (Ziegler 2009).
• Diabetes: Use hydrochlorothiazide with caution in patients with prediabetes or diabetes mellitus; may see a change in glucose control.
• Gout: In certain patients with a history of gout, a familial predisposition to gout, or chronic renal failure, gout can be precipitated by hydrochlorothiazide. This risk may be increased with doses ≥25 mg (Gurwitz 1997).
• Hepatic impairment: Use is not recommended for initial therapy in patients with hepatic impairment. Use with caution in hepatic impairment or progressive hepatic disease; avoid electrolyte and acid/base imbalances that might lead to hepatic encephalopathy/coma.
• Hypercalcemia: Thiazide diuretics may decrease renal calcium excretion; consider avoiding use in patients with hypercalcemia.
• Hypercholesterolemia: Use with caution in patients with moderate or high cholesterol concentrations; increased cholesterol and triglyceride levels have been reported with thiazides.
• Parathyroid disease: Thiazide diuretics reduce calcium excretion; pathologic changes in the parathyroid glands with hypercalcemia and hypophosphatemia have been observed with prolonged use; should be discontinued prior to testing for parathyroid function.
• Renal artery stenosis: Use losartan with caution in patients with unstented unilateral/bilateral renal artery stenosis. When unstented bilateral renal artery stenosis is present, use is generally avoided due to the elevated risk of deterioration in renal function unless possible benefits outweigh risks.
• Renal impairment: Use losartan with caution with preexisting renal insufficiency. Avoid hydrochlorothiazide in severe renal disease (ineffective); may precipitate azotemia; discontinue or consider withholding if renal impairment occurs. Contraindicated in patients with anuria.
• Systemic lupus erythematosus (SLE): Hydrochlorothiazide can cause SLE exacerbation or activation.
Special populations:
• Black patients: In Black patients, the BP-lowering effects of ARBs (eg, losartan) may be less pronounced. The exact mechanism is not known; differences in the renin-angiotensin-aldosterone system, low renin levels, and salt sensitivity more commonly found in Black patients may contribute. Evidence suggests that an alternative agent (ie, atenolol) may be a more beneficial initial treatment option in Black patients (Brewster 2013; Helmer 2018; Julius 2004; manufacturer's labeling).
• Surgical patients: In patients on chronic angiotensin receptor blocker (ARB) therapy, intraoperative hypotension may occur with induction and maintenance of general anesthesia; however, discontinuation of therapy prior to surgery is controversial. If continued preoperatively, avoidance of hypotensive agents during surgery is prudent (Hillis, 2011).
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral:
Hyzaar 50/12.5: Losartan potassium 50 mg and hydrochlorothiazide 12.5 mg [contains potassium 4.24 mg (0.108 mEq)]
Hyzaar 100/12.5: Losartan potassium 100 mg and hydrochlorothiazide 12.5 mg [contains potassium 8.48 mg (0.216 mEq)]
Hyzaar 100/25: Losartan potassium 100 mg and hydrochlorothiazide 25 mg [contains potassium 8.48 mg (0.216 mEq)]
Generic: 50/12.5: Losartan potassium 50 mg and hydrochlorothiazide 12.5 mg; 100/12.5: Losartan potassium 100 mg and hydrochlorothiazide 12.5 mg; 100/25: Losartan potassium 100 mg and hydrochlorothiazide 25 mg
Yes
Tablets (Hyzaar Oral)
50-12.5 mg (per each): $5.94
100-12.5 mg (per each): $8.11
100-25 mg (per each): $8.11
Tablets (Losartan Potassium-HCTZ Oral)
50-12.5 mg (per each): $2.50
100-12.5 mg (per each): $3.41
100-25 mg (per each): $3.41
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Administer without regard to meals; however, administer consistently with respect to food intake at about the same time every day.
Hypertension: Management of hypertension.
Hypertension with left ventricular hypertrophy: To reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy (LVH). Evidence suggests that an alternative agent (ie, atenolol) may be a more beneficial initial treatment option in Black patients (Dahlöf 2002; Julius 2004).
Hyzaar may be confused with Cozaar
Beers Criteria: Diuretics (hydrochlorothiazide) are identified in the Beers Criteria as potentially inappropriate medications to be used with caution in patients 65 years and older because of the potential to cause or exacerbate syndrome of inappropriate antidiuretic hormone secretion (SIADH) or hyponatremia; monitor sodium concentration closely when initiating or adjusting the dose in older adults (Beers Criteria [AGS 2023]).
Refer to individual components.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Agents with Clinically Relevant Anticholinergic Effects: May increase serum concentration of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Ajmaline: Sulfonamides may increase adverse/toxic effects of Ajmaline. Specifically, the risk for cholestasis may be increased. Risk C: Monitor
Alcohol (Ethyl): May increase orthostatic hypotensive effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Alfuzosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Aliskiren: May increase nephrotoxic effects of Angiotensin II Receptor Blockers. Aliskiren may increase hyperkalemic effects of Angiotensin II Receptor Blockers. Aliskiren may increase hypotensive effects of Angiotensin II Receptor Blockers. Management: Aliskiren use with ACEIs or ARBs in patients with diabetes is contraindicated. Combined use in other patients should be avoided, particularly when CrCl is less than 60 mL/min. If combined, monitor potassium, creatinine, and blood pressure closely. Risk D: Consider Therapy Modification
Allopurinol: Thiazide and Thiazide-Like Diuretics may increase hypersensitivity effects of Allopurinol. Risk C: Monitor
Amifostine: Blood Pressure Lowering Agents may increase hypotensive effects of Amifostine. Management: When used at chemotherapy doses, hold blood pressure lowering medications for 24 hours before amifostine administration. If blood pressure lowering therapy cannot be held, do not administer amifostine. Use caution with radiotherapy doses of amifostine. Risk D: Consider Therapy Modification
Aminolevulinic Acid (Systemic): Photosensitizing Agents may increase photosensitizing effects of Aminolevulinic Acid (Systemic). Risk X: Avoid
Aminolevulinic Acid (Topical): Photosensitizing Agents may increase photosensitizing effects of Aminolevulinic Acid (Topical). Risk C: Monitor
Amphetamines: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Angiotensin II: Angiotensin II Receptor Blockers may decrease therapeutic effects of Angiotensin II. Risk C: Monitor
Angiotensin-Converting Enzyme Inhibitors: Angiotensin II Receptor Blockers may increase adverse/toxic effects of Angiotensin-Converting Enzyme Inhibitors. Angiotensin II Receptor Blockers may increase serum concentration of Angiotensin-Converting Enzyme Inhibitors. Management: Use of telmisartan and ramipril is not recommended. It is not clear if any other combination of an ACE inhibitor and an ARB would be any safer. Consider alternatives when possible. Monitor blood pressure, renal function, and potassium if combined. Risk D: Consider Therapy Modification
Antidiabetic Agents: Hyperglycemia-Associated Agents may decrease therapeutic effects of Antidiabetic Agents. Risk C: Monitor
Antidiabetic Agents: Thiazide and Thiazide-Like Diuretics may decrease therapeutic effects of Antidiabetic Agents. Risk C: Monitor
Antihepaciviral Combination Products: May increase serum concentration of Losartan. Management: Consider decreasing the losartan dose and monitoring for evidence of hypotension and worsening renal function if these agents are used in combination. Risk D: Consider Therapy Modification
Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may increase hypotensive effects of Antipsychotic Agents (Second Generation [Atypical]). Risk C: Monitor
Arginine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Arsenic Trioxide: Thiazide and Thiazide-Like Diuretics may increase hypotensive effects of Arsenic Trioxide. Thiazide and Thiazide-Like Diuretics may increase QTc-prolonging effects of Arsenic Trioxide. Management: When possible, avoid concurrent use of arsenic trioxide with drugs that can cause electrolyte abnormalities, such as the thiazide and thiazide-like diuretics. Risk D: Consider Therapy Modification
Barbiturates: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Benperidol: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Berberine-Containing Products: May increase hypotensive effects of Losartan. Berberine-Containing Products may increase serum concentration of Losartan. Risk C: Monitor
Beta2-Agonists: May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Bile Acid Sequestrants: May decrease absorption of Thiazide and Thiazide-Like Diuretics. Management: Separate administration of bile acid sequestrants and oral thiazide diuretics by at least 4 hours. Monitor for decreased therapeutic effects of thiazide diuretics if coadministered with a bile acid sequestrant. Risk D: Consider Therapy Modification
Brigatinib: May decrease antihypertensive effects of Antihypertensive Agents. Brigatinib may increase bradycardic effects of Antihypertensive Agents. Risk C: Monitor
Brimonidine (Topical): May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Bromperidol: May decrease hypotensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase hypotensive effects of Bromperidol. Risk X: Avoid
Calcium Salts: Thiazide and Thiazide-Like Diuretics may increase serum concentration of Calcium Salts. Risk C: Monitor
Cardiac Glycosides: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Cardiac Glycosides. Specifically, cardiac glycoside toxicity may be enhanced by the hypokalemic and hypomagnesemic effect of thiazide diuretics. Risk C: Monitor
Corticosteroids (Systemic): May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
CycloPHOSphamide: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of CycloPHOSphamide. Specifically, granulocytopenia may be enhanced. Risk C: Monitor
CYP2C9 Inhibitors (Moderate): May increase serum concentration of Losartan. CYP2C9 Inhibitors (Moderate) may decrease active metabolite exposure of Losartan. Risk C: Monitor
Dapoxetine: May increase orthostatic hypotensive effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Desmopressin: Hyponatremia-Associated Agents may increase hyponatremic effects of Desmopressin. Risk C: Monitor
Dexketoprofen: May increase adverse/toxic effects of Sulfonamides. Risk C: Monitor
Dexmethylphenidate: May decrease therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Diacerein: May increase therapeutic effects of Diuretics. Specifically, the risk for dehydration or hypokalemia may be increased. Risk C: Monitor
Diazoxide Choline: May increase adverse/toxic effects of Thiazide and Thiazide-Like Diuretics. Specifically, the hyperglycemic and hyperuricemic effects may be increased. Risk C: Monitor
Diazoxide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Diazoxide: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Diazoxide. Risk C: Monitor
Dichlorphenamide: Thiazide and Thiazide-Like Diuretics may increase hypokalemic effects of Dichlorphenamide. Risk C: Monitor
Dipeptidyl Peptidase-IV Inhibitors: May increase adverse/toxic effects of Angiotensin II Receptor Blockers. Specifically, the risk for angioedema may be increased with this combination. Risk C: Monitor
Dofetilide: HydroCHLOROthiazide may increase QTc-prolonging effects of Dofetilide. HydroCHLOROthiazide may increase serum concentration of Dofetilide. Risk X: Avoid
Drospirenone-Containing Products: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
DULoxetine: Blood Pressure Lowering Agents may increase hypotensive effects of DULoxetine. Risk C: Monitor
EPINEPHrine (Systemic): Diuretics may increase arrhythmogenic effects of EPINEPHrine (Systemic). Diuretics may decrease vasopressor effects of EPINEPHrine (Systemic). Risk C: Monitor
Finerenone: Angiotensin II Receptor Blockers may increase hyperkalemic effects of Finerenone. Risk C: Monitor
Flunarizine: May increase therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Heparin: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Heparins (Low Molecular Weight): May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Herbal Products with Blood Pressure Increasing Effects: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Herbal Products with Blood Pressure Lowering Effects: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Hypotension-Associated Agents: Blood Pressure Lowering Agents may increase hypotensive effects of Hypotension-Associated Agents. Risk C: Monitor
Iloperidone: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Indoramin: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Ipragliflozin: May increase adverse/toxic effects of Thiazide and Thiazide-Like Diuretics. Specifically, the risk for intravascular volume depletion may be increased. Risk C: Monitor
Isocarboxazid: May increase antihypertensive effects of Antihypertensive Agents. Risk X: Avoid
Isocarboxazid: May increase hypotensive effects of Diuretics. Risk X: Avoid
Ivabradine: Thiazide and Thiazide-Like Diuretics may increase arrhythmogenic effects of Ivabradine. Risk C: Monitor
Levodopa-Foslevodopa: Blood Pressure Lowering Agents may increase hypotensive effects of Levodopa-Foslevodopa. Risk C: Monitor
Levosulpiride: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Levosulpiride. Risk X: Avoid
Licorice: May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Lithium: Angiotensin II Receptor Blockers may increase serum concentration of Lithium. Management: Initiate lithium at lower doses in patients receiving an angiotensin II receptor blocker (ARB). Consider lithium dose reductions in patients stable on lithium therapy who are initiating an ARB. Monitor lithium concentrations closely when combined. Risk D: Consider Therapy Modification
Lithium: Thiazide and Thiazide-Like Diuretics may decrease excretion of Lithium. Management: Reduce the lithium dose if coadministered with thiazide or thiazide-like diuretics. Monitor serum lithium levels during coadministration with thiazide and thiazide-like diuretics. Risk D: Consider Therapy Modification
Loop Diuretics: May increase hypotensive effects of Angiotensin II Receptor Blockers. Loop Diuretics may increase nephrotoxic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Loop Diuretics: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Lormetazepam: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Lumacaftor and Ivacaftor: May decrease serum concentration of CYP2C9 Substrates (High Risk with Inhibitors or Inducers). Lumacaftor and Ivacaftor may increase serum concentration of CYP2C9 Substrates (High Risk with Inhibitors or Inducers). Risk C: Monitor
Mecamylamine: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Mecamylamine. Management: Consider avoiding the use of mecamylamine and thiazide diuretics. If combined, mecamylamine prescribing information suggests reducing the mecamylamine dose by 50% in order to avoid excessive hypotension. Risk D: Consider Therapy Modification
Metergoline: May decrease antihypertensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase orthostatic hypotensive effects of Metergoline. Risk C: Monitor
Methenamine: Thiazide and Thiazide-Like Diuretics may decrease therapeutic effects of Methenamine. Risk C: Monitor
Methotrexate: HydroCHLOROthiazide may increase nephrotoxic effects of Methotrexate. Risk C: Monitor
Methoxsalen (Systemic): Photosensitizing Agents may increase photosensitizing effects of Methoxsalen (Systemic). Risk C: Monitor
Methylphenidate: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Molsidomine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Multivitamins/Fluoride (with ADE): May increase hypercalcemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Multivitamins/Minerals (with ADEK, Folate, Iron): Thiazide and Thiazide-Like Diuretics may increase hypercalcemic effects of Multivitamins/Minerals (with ADEK, Folate, Iron). Risk C: Monitor
Multivitamins/Minerals (with AE, No Iron): Thiazide and Thiazide-Like Diuretics may increase serum concentration of Multivitamins/Minerals (with AE, No Iron). Specifically, thiazide diuretics may decrease the excretion of calcium, and continued concomitant use can also result in metabolic alkalosis. Risk C: Monitor
Naftopidil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Neuromuscular-Blocking Agents (Nondepolarizing): Thiazide and Thiazide-Like Diuretics may increase neuromuscular-blocking effects of Neuromuscular-Blocking Agents (Nondepolarizing). Risk C: Monitor
Nicergoline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicorandil: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Nicorandil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nitroprusside: Blood Pressure Lowering Agents may increase hypotensive effects of Nitroprusside. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents (Topical): May decrease therapeutic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents (Topical): May decrease therapeutic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: May decrease therapeutic effects of Angiotensin II Receptor Blockers. The combination of these two agents may also significantly decrease glomerular filtration and renal function. Angiotensin II Receptor Blockers may increase adverse/toxic effects of Nonsteroidal Anti-Inflammatory Agents. Specifically, the combination may result in a significant decrease in renal function. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: May decrease therapeutic effects of Thiazide and Thiazide-Like Diuretics. Thiazide and Thiazide-Like Diuretics may increase nephrotoxic effects of Nonsteroidal Anti-Inflammatory Agents. Risk C: Monitor
Obinutuzumab: May increase hypotensive effects of Blood Pressure Lowering Agents. Management: Consider temporarily withholding blood pressure lowering medications beginning 12 hours prior to obinutuzumab infusion and continuing until 1 hour after the end of the infusion. Risk D: Consider Therapy Modification
Opioid Agonists: May increase adverse/toxic effects of Diuretics. Opioid Agonists may decrease therapeutic effects of Diuretics. Risk C: Monitor
Palopegteriparatide: Thiazide and Thiazide-Like Diuretics may increase therapeutic effects of Palopegteriparatide. Thiazide and Thiazide-Like Diuretics may decrease therapeutic effects of Palopegteriparatide. Risk C: Monitor
Pentoxifylline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Perazine: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Pholcodine: Blood Pressure Lowering Agents may increase hypotensive effects of Pholcodine. Risk C: Monitor
Phosphodiesterase 5 Inhibitors: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Piperacillin: May increase hypokalemic effects of Diuretics. Risk C: Monitor
Polyethylene Glycol-Electrolyte Solution: Angiotensin II Receptor Blockers may increase nephrotoxic effects of Polyethylene Glycol-Electrolyte Solution. Risk C: Monitor
Polyethylene Glycol-Electrolyte Solution: Diuretics may increase nephrotoxic effects of Polyethylene Glycol-Electrolyte Solution. Risk C: Monitor
Porfimer: Photosensitizing Agents may increase photosensitizing effects of Porfimer. Risk X: Avoid
Potassium Salts: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Potassium-Sparing Diuretics: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Prazosin: Antihypertensive Agents may increase hypotensive effects of Prazosin. Risk C: Monitor
Promazine: Thiazide and Thiazide-Like Diuretics may increase QTc-prolonging effects of Promazine. Risk X: Avoid
Prostacyclin Analogues: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Quinagolide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Ranolazine: May increase adverse/toxic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Reboxetine: May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Sacubitril: Angiotensin II Receptor Blockers may increase adverse/toxic effects of Sacubitril. Risk X: Avoid
Selective Serotonin Reuptake Inhibitor: May increase hyponatremic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Silodosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Sodium Phosphates: Angiotensin II Receptor Blockers may increase nephrotoxic effects of Sodium Phosphates. Specifically, the risk of acute phosphate nephropathy may be enhanced. Risk C: Monitor
Sodium Phosphates: Diuretics may increase nephrotoxic effects of Sodium Phosphates. Specifically, the risk of acute phosphate nephropathy may be enhanced. Risk C: Monitor
Sotagliflozin: HydroCHLOROthiazide may decrease therapeutic effects of Sotagliflozin. Sotagliflozin may decrease serum concentration of HydroCHLOROthiazide. Risk C: Monitor
Sparsentan: May increase adverse/toxic effects of Angiotensin II Receptor Blockers. Risk X: Avoid
Tacrolimus (Systemic): Angiotensin II Receptor Blockers may increase hyperkalemic effects of Tacrolimus (Systemic). Risk C: Monitor
Terazosin: Antihypertensive Agents may increase hypotensive effects of Terazosin. Risk C: Monitor
Tolvaptan: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Topiramate: Thiazide and Thiazide-Like Diuretics may increase hypokalemic effects of Topiramate. Thiazide and Thiazide-Like Diuretics may increase serum concentration of Topiramate. Risk C: Monitor
Toremifene: Thiazide and Thiazide-Like Diuretics may increase hypercalcemic effects of Toremifene. Risk C: Monitor
Trimethoprim: May increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Urapidil: Antihypertensive Agents may increase hypotensive effects of Urapidil. Risk C: Monitor
Vanzacaftor, Tezacaftor, and Deutivacaftor: May increase serum concentration of CYP2C9 Substrates (High risk with Inhibitors). Risk C: Monitor
Verteporfin: Photosensitizing Agents may increase photosensitizing effects of Verteporfin. Risk C: Monitor
Vitamin D Analogs: Thiazide and Thiazide-Like Diuretics may increase hypercalcemic effects of Vitamin D Analogs. Risk C: Monitor
[US Boxed Warning]: Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus. When pregnancy is detected, discontinue therapy as soon as possible.
Refer to individual monographs for additional information.
It is not known if losartan is excreted in breast milk; thiazide diuretics are excreted in breast milk.
Due to the potential for serious adverse reactions in the breastfed infant, the manufacturer recommends a decision be made whether to discontinue breastfeeding or to discontinue the drug, taking into account the importance of treatment to the mother.
Refer to individual monographs for additional information.
Some products may contain potassium.
Baseline and periodic BP, serum electrolytes, renal function, visual acuity, ocular pain.
Losartan: As a selective and competitive, nonpeptide angiotensin II receptor antagonist, losartan blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II; losartan interacts reversibly at the AT1 and AT2 receptors of many tissues and has slow dissociation kinetics; its affinity for the AT1 receptor is 1000 times greater than the AT2 receptor. Angiotensin II receptor antagonists may induce a more complete inhibition of the renin-angiotensin system than ACE inhibitors, they do not affect the response to bradykinin, and are less likely to be associated with nonrenin-angiotensin effects (eg, cough and angioedema). Losartan increases urinary flow rate and in addition to being natriuretic and kaliuretic, increases excretion of chloride, magnesium, uric acid, calcium, and phosphate.
Hydrochlorothiazide: Inhibits sodium reabsorption in the distal tubules causing increased excretion of sodium and water as well as potassium and hydrogen ions.
See individual agents.