Quinapril hydrochloride/Hydrochlorothiazide

Description

Quinapril HCl and hydrochlorothiazide tablets, USP are fixed-combination tablets that incorporate quinapril hydrochloride, an angiotensin-converting enzyme (ACE) inhibitor, and hydrochlorothiazide, a thiazide diuretic. Quinapril hydrochloride, USP is chemically defined as [3S-[2R*(R*), 3R*]]-2-[2-[1-(ethoxycarbonyl)-3-phenylpropyl amino]-1-oxopropyl]-1, 2, 3, 4-tetrahydro-3-isoquinolinecarboxylic acid, monohydrochloride, with an empirical formula of C25H30N2O5·HCl. It appears as a white to off-white amorphous powder that is freely soluble in aqueous solvents. Hydrochlorothiazide, USP is characterized as 6-Chloro-3, 4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide, with an empirical formula of C7H8ClN3O4S2. This compound is a white to off-white crystalline powder, slightly soluble in water but freely soluble in sodium hydroxide solution.

These tablets are formulated for oral administration and are available in three strengths: 10 mg of quinapril with 12.5 mg of hydrochlorothiazide (quinapril HCl and hydrochlorothiazide 10/12.5), 20 mg of quinapril with 12.5 mg of hydrochlorothiazide (quinapril HCl and hydrochlorothiazide 20/12.5), and 20 mg of quinapril with 25 mg of hydrochlorothiazide (quinapril HCl and hydrochlorothiazide 20/25). Inactive ingredients include lactose, magnesium carbonate, crospovidone, povidone, magnesium stearate, and opadry pink 03B14436, which consists of hypromellose, titanium dioxide, polyethylene glycol, and iron oxide red.

Uses and Indications

Quinapril HCl and hydrochlorothiazide tablets, USP are indicated for the treatment of hypertension to lower blood pressure. Effective management of high blood pressure is essential in reducing the risk of both fatal and nonfatal cardiovascular events, particularly strokes and myocardial infarctions.

Control of hypertension should be integrated into a comprehensive cardiovascular risk management strategy, which includes lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. It is important to note that many patients may require a combination of antihypertensive medications to achieve their blood pressure goals.

Numerous antihypertensive agents have demonstrated efficacy in randomized controlled trials, showing a reduction in cardiovascular morbidity and mortality. The most significant cardiovascular outcome benefit observed is a decrease in the risk of stroke, along with reductions in myocardial infarction and overall cardiovascular mortality. Elevated systolic or diastolic blood pressure is associated with increased cardiovascular risk, and even modest reductions in severe hypertension can yield substantial health benefits.

The relative risk reduction associated with blood pressure lowering is consistent across various populations with differing absolute risks, with patients at higher risk experiencing greater absolute benefits, regardless of their hypertension status. It is also noted that some antihypertensive medications may exhibit diminished blood pressure-lowering effects in black patients, and many of these agents have additional approved indications for conditions such as angina, heart failure, or diabetic kidney disease.

This fixed combination of Quinapril HCl and hydrochlorothiazide is not indicated for the initial therapy of hypertension.

Dosage and Administration

Quinapril may be administered as monotherapy at a dosage range of 10 to 80 mg once daily. Hydrochlorothiazide can be prescribed as monotherapy at a dosage range of 12.5 to 50 mg once daily. For patients requiring combination therapy, quinapril should be dosed between 2.5 to 40 mg, while hydrochlorothiazide should be dosed between 6.25 to 25 mg.

For patients not adequately controlled with quinapril monotherapy, quinapril HCl and hydrochlorothiazide tablets are available in formulations of 10/12.5 mg or 20/12.5 mg. Adjustments to the dosage of either component may be made based on clinical response, although increases in hydrochlorothiazide should generally not occur until 2 to 3 weeks have elapsed.

In cases of replacement therapy, quinapril HCl and hydrochlorothiazide tablets at a dosage of 20/25 mg may be utilized for patients who have been adequately treated with 20 mg of quinapril and 25 mg of hydrochlorothiazide, provided there are no significant electrolyte disturbances.

All formulations should be administered orally once daily.

Contraindications

Quinapril HCl and hydrochlorothiazide tablets are contraindicated in patients with a known hypersensitivity to quinapril or hydrochlorothiazide, as well as in those with a history of angioedema associated with prior ACE inhibitor therapy. The presence of hydrochlorothiazide also contraindicates use in patients with anuria or hypersensitivity to sulfonamide-derived drugs. Additionally, co-administration with aliskiren is contraindicated in patients with diabetes due to potential adverse effects.

Warnings and Precautions

Patients receiving ACE inhibitors, including quinapril HCl and hydrochlorothiazide tablets, may experience a range of serious adverse reactions. Anaphylactoid reactions, which can be life-threatening, have been reported. Healthcare professionals should be vigilant for signs of angioedema, particularly in the head and neck region. Angioedema affecting the face, extremities, lips, tongue, glottis, and larynx has been documented, with laryngeal edema posing a risk of fatality. In the event of laryngeal stridor or angioedema involving the face, tongue, or glottis, treatment with quinapril HCl and hydrochlorothiazide tablets must be discontinued immediately, and emergency therapy, including subcutaneous epinephrine solution 1:1000 (0.3 to 0.5 mL), should be administered without delay.

Intestinal angioedema has also been reported in patients treated with ACE inhibitors, with symptoms resolving upon discontinuation of the medication. Patients with a history of angioedema unrelated to ACE inhibitor therapy may be at an increased risk for similar reactions while on treatment. Additionally, life-threatening anaphylactoid reactions have occurred in patients undergoing desensitization therapy while receiving ACE inhibitors.

Hepatic failure, although rare, has been associated with ACE inhibitors, beginning with cholestatic jaundice and potentially progressing to fulminant hepatic necrosis and death. Patients developing jaundice or significant elevations in hepatic enzymes should discontinue the ACE inhibitor and receive appropriate medical follow-up.

Quinapril HCl and hydrochlorothiazide tablets can induce symptomatic hypotension, particularly in patients with heart failure, hyponatremia, high-dose diuretic therapy, recent intensive diuresis, renal dialysis, or severe volume and/or salt depletion. Caution is advised when prescribing these medications to patients with severe renal disease, as changes in renal function may occur.

Neutropenia and agranulocytosis have been observed, warranting periodic monitoring of white blood cell counts in patients with collagen vascular disease and/or renal disease. Furthermore, the use of drugs affecting the renin-angiotensin system during the second and third trimesters of pregnancy can result in fetal injury or death; therefore, quinapril HCl and hydrochlorothiazide tablets should be discontinued as soon as pregnancy is detected.

General precautions include the need for periodic monitoring of serum electrolytes, as hyperkalemia has been reported in approximately 2% of patients receiving quinapril, while hydrochlorothiazide may lead to hypokalemia and hyponatremia. Hydrochlorothiazide may also affect glucose tolerance and elevate serum cholesterol, triglycerides, and uric acid levels, potentially exacerbating hyperuricemia. A persistent nonproductive cough has been noted with all ACE inhibitors, typically resolving after discontinuation of therapy.

During surgical procedures or anesthesia, quinapril may inhibit the formation of angiotensin II, which could otherwise occur due to compensatory renin release. It is advisable to interrupt therapy with quinapril HCl and hydrochlorothiazide tablets for several days prior to conducting tests of parathyroid function, as the hydrochlorothiazide component may decrease serum PBI levels without indicating thyroid disturbance.

In summary, healthcare professionals should remain alert to the potential for serious adverse reactions associated with quinapril HCl and hydrochlorothiazide tablets, ensuring appropriate monitoring and intervention as necessary.

Side Effects

Patients receiving the medication may experience a range of adverse reactions. Common adverse reactions, occurring in 1% or more of patients, include headache, dizziness, coughing, fatigue, myalgia, viral infection, rhinitis, nausea and/or vomiting, abdominal pain, back pain, diarrhea, upper respiratory infection, insomnia, somnolence, bronchitis, dyspepsia, asthenia, pharyngitis, vasodilatation, vertigo, and chest pain.

Clinical adverse experiences occurring in 0.5% to less than 1.0% of patients include a variety of symptoms across different systems. In the body as a whole, asthenia and malaise have been noted. Cardiovascular events may include palpitations, tachycardia, heart failure, hyperkalemia, myocardial infarction, cerebrovascular accident, hypertensive crisis, angina pectoris, orthostatic hypotension, and cardiac rhythm disturbances. Gastrointestinal issues may manifest as dry mouth or throat, gastrointestinal hemorrhage, pancreatitis, and abnormal liver function tests. Nervous and psychiatric reactions include nervousness, vertigo, and paresthesia. Respiratory symptoms may consist of sinusitis and dyspnea. Integumentary reactions can include pruritus, increased sweating, erythema multiforme, exfoliative dermatitis, photosensitivity reactions, alopecia, and pemphigus. Urogenital system reactions may involve acute renal failure and impotence. Other notable reactions include agranulocytosis, thrombocytopenia, and arthralgia.

Angioedema has been reported in 0.1% of patients receiving quinapril.

Postmarketing experience has revealed additional adverse reactions. In the body as a whole, reports include shock, accidental injury, neoplasm, cellulitis, ascites, generalized edema, hernia, and anaphylactoid reactions. Cardiovascular system reactions may involve bradycardia, cor pulmonale, vasculitis, and deep thrombosis. The digestive system may experience gastrointestinal carcinoma, cholestatic jaundice, hepatitis, esophagitis, vomiting, and diarrhea. Eye disorders reported include acute myopia and acute angle closure glaucoma. Hemic system reactions may present as anemia. Metabolic and nutritional disorders may lead to weight loss. Musculoskeletal system reactions can include myopathy, myositis, and arthritis. Neurological reactions may consist of paralysis, hemiplegia, speech disorders, abnormal gait, meningism, and amnesia. Respiratory system issues may include pneumonia, asthma, respiratory infiltration, and lung disorders. Skin and appendage reactions can manifest as urticaria, macropapular rash, and petechiae. Special senses may be affected by abnormal vision. Urogenital system reactions may include kidney function abnormalities, albuminuria, pyuria, hematuria, and nephrosis.

Hypersensitivity reactions have also been noted, including necrotizing angiitis, Stevens-Johnson syndrome, respiratory distress (including pneumonitis and pulmonary edema), purpura, urticaria, rash, and photosensitivity. A persistent nonproductive cough has been reported with all ACE inhibitors, typically resolving after discontinuation of therapy. Symptomatic hypotension was observed in 1.2% of patients during clinical trials.

Drug Interactions

Coadministration of quinapril HCl and hydrochlorothiazide tablets with agents that increase serum potassium levels may lead to hyperkalemia. It is advised to monitor serum potassium levels in patients receiving such combinations.

When quinapril HCl and hydrochlorothiazide tablets are used concurrently with lithium, there is an increased risk of elevated serum lithium levels and potential lithium toxicity. This risk is further heightened due to the renal clearance reduction of lithium caused by thiazides. Therefore, caution is warranted when coadministering these agents, and frequent monitoring of serum lithium levels is recommended.

The use of quinapril HCl and hydrochlorothiazide tablets in conjunction with other agents that block the renin-angiotensin system (RAS), such as angiotensin receptor blockers or aliskiren, is associated with an increased risk of hypotension, hyperkalemia, and renal function changes, including acute renal failure. Most patients do not derive additional benefits from dual RAS blockade compared to monotherapy. It is generally recommended to avoid the combined use of RAS inhibitors. Patients on this combination should have their blood pressure, renal function, and electrolytes closely monitored. Specifically, aliskiren should not be coadministered with quinapril HCl and hydrochlorothiazide tablets in patients with diabetes or renal impairment (GFR <60 mL/min/1.73 m²).

The simultaneous administration of tetracycline with quinapril may reduce the absorption of tetracycline by approximately 28% to 37%, likely due to the high magnesium content in quinapril tablets. This interaction should be considered when coprescribing these medications.

Rare instances of nitritoid reactions, characterized by facial flushing, nausea, vomiting, and hypotension, have been reported in patients receiving injectable gold (sodium aurothiomalate) alongside ACE inhibitors.

In elderly patients, those who are volume-depleted, or individuals with compromised renal function, the coadministration of non-steroidal anti-inflammatory drugs (NSAIDs), including selective COX-2 inhibitors, with ACE inhibitors like quinapril may lead to renal function deterioration, potentially resulting in acute renal failure. These effects are typically reversible, but renal function should be monitored periodically in patients receiving this combination. Additionally, the antihypertensive effect of ACE inhibitors may be diminished by NSAIDs.

Patients receiving mTOR inhibitors, such as temsirolimus, may experience an increased risk of angioedema when taking quinapril HCl and hydrochlorothiazide tablets.

Other interactions include:

• Propranolol and cimetidine do not significantly affect the pharmacokinetics of quinapril when administered in multiple doses.

• The anticoagulant effect of warfarin, as measured by prothrombin time, is not significantly altered by the coadministration of quinapril.

• No pharmacokinetic interaction is observed when single doses of quinapril and hydrochlorothiazide are administered together.

Thiazide-induced electrolyte disturbances, such as hypokalemia and hypomagnesemia, can increase the risk of digoxin toxicity, potentially leading to fatal arrhythmias.

Several drugs may interact with thiazide diuretics, including:

• Alcohol, barbiturates, or narcotics, which may potentiate orthostatic hypotension.

• Antidiabetic agents, which may require dosage adjustments.

• Cholestyramine and colestipol resins, which can significantly impair the absorption of hydrochlorothiazide.

• Corticosteroids and ACTH, which may intensify electrolyte depletion, particularly hypokalemia.

• Pressor amines (e.g., norepinephrine), which may have a decreased response but can still be used therapeutically.

• Non-depolarizing skeletal muscle relaxants (e.g., tubocurarine), which may show increased responsiveness.

• Non-steroidal anti-inflammatory drugs, which may reduce the diuretic, natriuretic, and antihypertensive effects of thiazide diuretics.

Packaging & NDC

The table below lists all NDC Code configurations of Quinapril Hydrochloride and Hydrochlorothiazide, the U.S. brand-name prescription product. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

Pediatric patients, particularly neonates with a history of in utero exposure to quinapril HCl and hydrochlorothiazide tablets, may experience complications such as oliguria or hypotension. In such cases, it is crucial to provide support for blood pressure and renal perfusion. Interventions such as exchange transfusions or dialysis may be necessary to address hypotension and/or to manage impaired renal function. It is important to note that the removal of quinapril from the neonatal circulation, which can cross the placenta, is not significantly accelerated by these interventions.

The safety and effectiveness of quinapril HCl and hydrochlorothiazide tablets in children have not been established, indicating a need for caution when considering this treatment in pediatric populations.

Geriatric Use

Clinical studies of quinapril HCl and hydrochlorothiazide did not include a sufficient number of subjects aged 65 and over to determine whether these elderly patients respond differently from younger subjects. However, other reported clinical experience has not identified significant differences in responses between elderly and younger patients.

In general, dose selection for geriatric patients should be approached with caution. It is advisable to start at the low end of the dosing range, taking into account the increased likelihood of decreased hepatic, renal, or cardiac function, as well as the presence of concomitant diseases or other drug therapies. Careful monitoring of these patients is recommended to ensure safety and efficacy.

Pregnancy

Pregnant patients should be aware that there is no specific information regarding the use of this medication during pregnancy, including safety concerns, dosage modifications, or special precautions. The prescribing information does not indicate any contraindications for use in pregnancy or any known risks to the fetus. Healthcare professionals are encouraged to consider the absence of data when advising women of childbearing potential and to weigh the potential benefits against any unknown risks when prescribing this medication to pregnant patients.

Lactation

Quinapril and hydrochlorothiazide are secreted in human milk; therefore, caution should be exercised when administering quinapril HCl and hydrochlorothiazide tablets to lactating mothers. Due to the potential for serious adverse reactions in breastfed infants from hydrochlorothiazide, along with the unknown effects of quinapril in infants, a decision should be made regarding whether to discontinue nursing or to discontinue the use of quinapril HCl and hydrochlorothiazide tablets. This decision should consider the importance of the medication to the mother.

Renal Impairment

Quinapril HCl and hydrochlorothiazide tablets should be used with caution in patients with severe renal disease, as thiazides may precipitate azotemia in these individuals, and the effects of repeated dosing may be cumulative. In patients with severe congestive heart failure, where renal function may depend on the renin-angiotensin-aldosterone system, inhibition by quinapril may lead to anticipated changes in renal function, including oliguria, progressive azotemia, and, in rare cases, acute renal failure or death.

Clinical studies have shown that hypertensive patients with unilateral renal artery stenosis treated with ACE inhibitors, including quinapril, experienced increases in blood urea nitrogen and serum creatinine, which were reversible upon discontinuation of the medication or concomitant diuretic. Therefore, renal function should be closely monitored during the initial weeks of therapy in such patients.

Additionally, some hypertensive patients treated with quinapril, even without apparent preexisting renal vascular diseases, have developed minor and transient increases in blood urea nitrogen and serum creatinine, particularly when quinapril is administered with a diuretic. This occurrence is more likely in patients with pre-existing renal impairment, and dosage reduction of quinapril HCl and hydrochlorothiazide tablets may be necessary. Regular assessment of renal function is recommended for these patients.

Finally, periodic monitoring of white blood cell counts should be considered in patients with collagen vascular disease and/or renal disease due to the associated risk of agranulocytosis and bone marrow depression linked to ACE inhibitors.

Hepatic Impairment

Quinapril HCl and hydrochlorothiazide tablets should be used with caution in patients with impaired hepatic function or progressive liver disease, as minor alterations in fluid and electrolyte balance may precipitate hepatic coma. The metabolism of quinapril to its active form, quinaprilat, is primarily dependent on hepatic esterases; therefore, patients with compromised liver function may experience markedly elevated plasma levels of quinapril.

Currently, no pharmacokinetic studies have been conducted specifically in hypertensive patients with impaired liver function, which limits the understanding of the drug's behavior in this population. Additionally, there is a rare association between ACE inhibitors and a syndrome that begins with cholestatic jaundice and can progress to fulminant hepatic necrosis, potentially resulting in death. Patients receiving ACE inhibitors who develop jaundice or significant elevations in hepatic enzymes should discontinue the use of the ACE inhibitor and receive appropriate medical follow-up.

Monitoring of liver function and careful assessment of fluid and electrolyte balance are recommended for patients with hepatic impairment receiving this medication.

Overdosage

In the event of an overdosage with quinapril HCl and hydrochlorothiazide tablets, specific treatment information is limited. Management should be primarily symptomatic and supportive. It is recommended that therapy with quinapril HCl and hydrochlorothiazide tablets be discontinued immediately, and the patient should be closely monitored for any adverse effects.

Potential Symptoms

The most likely manifestation of quinapril overdosage in humans is hypotension. In cases of hydrochlorothiazide overdose, common symptoms include dehydration and electrolyte depletion, which may present as hypokalemia, hypochloremia, and hyponatremia. If the patient has also received digitalis, hypokalemia may exacerbate the risk of cardiac arrhythmias.

Management Procedures

Treatment of dehydration, electrolyte imbalances, and hypotension should follow established medical protocols. The oral median lethal dose of quinapril and hydrochlorothiazide in combination has been observed to range from 1063/664 to 4640/2896 mg/kg in animal studies, with significant lethality noted at doses of 1440 to 4280 mg/kg of quinapril. In single-dose studies, most rats survived doses of hydrochlorothiazide up to 2.75 g/kg.

Laboratory assessments of serum levels of quinapril and its metabolites are not commonly available and do not play a defined role in the management of quinapril overdose. Furthermore, there is no evidence to support the use of physiological maneuvers, such as altering urine pH, to enhance the elimination of quinapril and its metabolites. Hemodialysis and peritoneal dialysis have been shown to have minimal impact on the elimination of quinapril and quinaprilat.

While angiotensin II could theoretically act as a specific antagonist or antidote in cases of quinapril overdose, it is largely unavailable outside of specialized research settings. Given that the hypotensive effects of quinapril result from vasodilation and effective hypovolemia, it is advisable to manage quinapril overdose with the infusion of normal saline solution to restore fluid balance.

Nonclinical Toxicology

Carcinogenicity, mutagenicity, and fertility studies have not been conducted in animals with quinapril HCl and hydrochlorothiazide tablets. Quinapril hydrochloride was not carcinogenic in mice or rats when administered at doses up to 75 or 100 mg/kg/day for 104 weeks, which corresponds to 50 or 60 times the maximum human daily dose on a mg/kg basis and 3.8 or 10 times the maximum human daily dose on a mg/m² basis. However, female rats receiving the highest dose level exhibited an increased incidence of mesenteric lymph node hemangiomas and skin/subcutaneous lipomas.

Neither quinapril nor quinaprilat demonstrated mutagenic potential in the Ames bacterial assay, both with and without metabolic activation. Quinapril was also negative in several genetic toxicology studies, including in vitro mammalian cell point mutation, sister chromatid exchange in cultured mammalian cells, micronucleus test with mice, in vitro chromosome aberration with V79 cultured lung cells, and an in vivo cytogenetic study with rat bone marrow. Additionally, there were no adverse effects on fertility or reproduction observed in rats at doses up to 100 mg/kg/day.

Under the auspices of the National Toxicology Program, hydrochlorothiazide was administered in feed to rats and mice for 2 years at doses up to 600 mg/kg/day in mice and up to 100 mg/kg/day in rats. These studies revealed no evidence of carcinogenic potential for hydrochlorothiazide in rats or female mice; however, there was equivocal evidence of hepatocarcinogenicity in male mice. Hydrochlorothiazide was not genotoxic in in vitro assays using various strains of Salmonella typhimurium, the Chinese hamster ovary test for chromosomal aberrations, or in vivo assays involving mouse germinal cell chromosomes and Chinese hamster bone marrow chromosomes.

Positive results were observed in the in vitro CHO sister chromatid exchange test and in the mouse lymphoma cell assays at concentrations of hydrochlorothiazide ranging from 43 to 1300 μg/mL. Additionally, positive results were obtained in the Aspergillus nidulans nondisjunction assay at an unspecified concentration. Hydrochlorothiazide did not adversely affect the fertility of mice and rats of either sex in studies where these species were exposed to doses of up to 100 and 4 mg/kg/day, respectively, prior to mating and throughout gestation.

Postmarketing Experience

During extensive postmarketing experience, the following serious nonfatal adverse events have been reported voluntarily or through surveillance programs, regardless of their relationship to quinapril and HCTZ combination tablets:

In the body as a whole, events such as shock, accidental injury, neoplasm, cellulitis, ascites, generalized edema, hernia, and anaphylactoid reaction have been documented. Cardiovascular system events include bradycardia, cor pulmonale, vasculitis, and deep thrombosis.

For the digestive system, reports include gastrointestinal carcinoma, cholestatic jaundice, hepatitis, esophagitis, vomiting, and diarrhea. Eye disorders noted are acute myopia and acute angle closure glaucoma (refer to WARNINGS).

In the hemic system, anemia has been reported. Metabolic and nutritional disorders include weight loss. Musculoskeletal system events consist of myopathy, myositis, and arthritis.

Nervous system events reported are paralysis, hemiplegia, speech disorder, abnormal gait, meningism, and amnesia. Respiratory system events include pneumonia, asthma, respiratory infiltration, and lung disorder.

Skin and appendages have shown reports of urticaria, macropapular rash, and petechiases. Special senses have been affected with reports of abnormal vision. Lastly, in the urogenital system, abnormalities in kidney function, albuminuria, pyuria, hematuria, and nephrosis have been documented.

Patient Counseling

Patients should be informed about the risk of angioedema, including laryngeal edema, which can occur with treatment using ACE inhibitors, particularly following the first dose. They should be advised to report immediately any signs or symptoms suggesting angioedema, such as swelling of the face, eyes, lips, or tongue, or difficulty in breathing. Patients must be instructed to refrain from taking any additional doses until they have consulted with their prescribing physician.

Female patients of childbearing age should be made aware of the potential consequences of exposure to quinapril HCl and hydrochlorothiazide tablets during pregnancy. It is important for them to discuss treatment options with their physician if they are planning to become pregnant and to report any pregnancies to their physician as soon as possible.

Patients receiving quinapril HCl and hydrochlorothiazide tablets should be cautioned that lightheadedness may occur, particularly during the initial days of therapy. They should be advised to report any instances of lightheadedness to their prescribing physician. In the event of syncope, patients should discontinue the medication and consult their physician before resuming treatment.

All patients should be cautioned that inadequate fluid intake, excessive perspiration, diarrhea, or vomiting can lead to a significant drop in blood pressure due to reduced fluid volume, which may result in lightheadedness and potential syncope.

Patients planning to undergo major surgery and/or general or spinal anesthesia should inform their physicians that they are taking an ACE inhibitor to ensure appropriate management during the procedure.

Patients should be advised against using potassium supplements or salt substitutes containing potassium without prior consultation with their prescribing physician.

Lastly, patients should be instructed to promptly report any signs of infection, such as a sore throat or fever, as these may indicate neutropenia and require immediate medical attention.

Storage and Handling

The product is supplied in accordance with the National Drug Code (NDC) specifications. It should be stored at a temperature range of 20°C to 25°C (68° to 77°F), adhering to the guidelines set forth by the United States Pharmacopeia (USP) for Controlled Room Temperature.

For optimal preservation, the product must be dispensed in tight containers as defined by the USP, ensuring the integrity and stability of the formulation during storage and handling.

Additional Clinical Information

The hydrochlorothiazide component of quinapril HCl and hydrochlorothiazide tablets may lead to a decrease in serum protein-bound iodine (PBI) levels, although this effect does not indicate any thyroid disturbance. Clinicians should consider interrupting therapy with quinapril HCl and hydrochlorothiazide tablets for several days prior to conducting tests to assess parathyroid function to ensure accurate results.

FDA Insert (PDF)

This document is the official FDA-approved prescribing information for Quinapril Hydrochloride and Hydrochlorothiazide as submitted by Camber Pharmaceuticals. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)