Candesartan cilexetil and hydrochlorothiazide tablets are contraindicated in patients who are hypersensitive to candesartan, to hydrochlorothiazide or to other sulfonamide-derived drugs.
Candesartan cilexetil and hydrochlorothiazide tablets are contraindicated in patients with anuria.
Pregnancy Category D
Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue candesartan cilexetil and hydrochlorothiazide tablets as soon as possible. These adverse outcomes are usually associated with use of these drugs in the second and third trimester of pregnancy. Most epidemiologic studies examining fetal abnormalities after exposure to antihypertensive use in the first trimester have not distinguished drugs affecting the renin-angiotensin system from other antihypertensive agents. Appropriate management of maternal hypertension during pregnancy is important to optimize outcomes for both mother and fetus.
In the unusual case that there is no appropriate alternative to therapy with drugs affecting the renin-angiotensin system for a particular patient, apprise the mother of the potential risk to the fetus. Perform serial ultrasound examinations to assess the intra-amniotic environment. If oligohydramnios is observed, discontinue candesartan cilexetil and hydrochlorothiazide tablets, unless it is considered lifesaving for the mother. Fetal testing may be appropriate, based on the week of pregnancy. Patients and physicians should be aware, however, that oligohydramnios may not appear until after the fetus has sustained irreversible injury. Closely observe infants with histories of in utero exposure to candesartan cilexetil and hydrochlorothiazide tablets for hypotension, oliguria, and hyperkalemia. (See PRECAUTIONS, Pediatric Use.)
There was no evidence of teratogenicity or other adverse effects on embryo-fetal development when pregnant mice, rats or rabbits were treated orally with candesartan cilexetil alone or in combination with hydrochlorothiazide. For mice, the maximum dose of candesartan cilexetil was 1000 mg/kg/day (about 150 times the maximum recommended daily human dose [MRHD]1). For rats, the maximum dose of candesartan cilexetil was 100 mg/kg/day (about 31 times the MRHD1). For rabbits, the maximum dose of candesartan cilexetil was 1 mg/kg/day (a maternally toxic dose that is about half the MRHD1). In each of these studies, hydrochlorothiazide was tested at the same dose level (10 mg/kg/day, about 4, 8, and 15 times the MRHD1 in mouse, rats, and rabbit, respectively). There was no evidence of harm to the rat or mouse fetus or embryo in studies in which hydrochlorothiazide was administered alone to the pregnant rat or mouse at doses of up to 1000 and 3000 mg/kg/day, respectively.
Thiazides cross the placental barrier and appear in cord blood. There is a risk of fetal or neonatal jaundice, thrombocytopenia, and possibly other adverse reactions that have occurred in adults.
- Doses compared on the basis of body surface area. MRHD considered to be 32 mg for candesartan cilexetil and 12.5 mg for hydrochlorothiazide.
Candesartan cilexetil and hydrochlorothiazide tablets can cause symptomatic hypotension. Symptomatic hypotension is most likely to occur in patients who have been volume and/or salt depleted as a result of prolonged diuretic therapy, dietary salt restriction, dialysis, diarrhea, or vomiting. Patients with symptomatic hypotension may require temporarily reducing the dose of candesartan cilexetil and hydrochlorothiazide tablets or volume repletion. Volume and/or salt depletion should be corrected before initiating therapy with candesartan cilexetil and hydrochlorothiazide tablets.
In patients with heart failure, candesartan cilexetil and hydrochlorothiazide tablets may cause excessive hypotension, which may lead to oliguria, azotemia, and (rarely) with acute renal failure and death (see WARNINGS, Impaired Renal Function). In such patients, candesartan cilexetil and hydrochlorothiazide tablets therapy should be started under close medical supervision; they should be followed closely for the first 2 weeks of treatment and whenever the dose of candesartan or diuretic is increased.
Monitor renal function periodically in patients treated with candesartan cilexetil and hydrochlorothiazide tablets. Changes in renal function including acute renal failure can be caused by drugs that inhibit the renin-angiotensin system and by diuretics. Patients whose renal function may depend in part on the activity of the renin-angiotensin system (e.g., patients with renal artery stenosis, chronic kidney disease, severe heart failure, or volume depletion) may be at particular risk of developing oliguria, progressive azotemia, or acute renal failure on candesartan cilexetil and hydrochlorothiazide tablets. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in renal function on candesartan cilexetil and hydrochlorothiazide tablets.
Drugs that inhibit the renin-angiotensin system can cause hyperkalemia. Hydrochlorothiazide can cause hypokalemia and hyponatremia. Hypomagnesemia can result in hypokalemia which appears difficult to treat despite potassium repletion. Monitor serum electrolytes periodically.
In clinical trials of various doses of candesartan cilexetil and hydrochlorothiazide, the incidence of hypertensive patients who developed hypokalemia (serum potassium <3.5 mEq/L) was 2.5% versus 2.1% for placebo; the incidence of hyperkalemia (serum potassium >5.7 mEq/L) was 0.4% versus 1.0% for placebo. No patient receiving candesartan cilexetil and hydrochlorothiazide tablets 16 mg/12.5 mg or 32 mg/12.5 mg was discontinued due to increases or decreases in serum potassium.
Hydrochlorothiazide, a sulfonamide, can cause an idiosyncratic reaction, resulting in acute transient myopia and acute angle-closure glaucoma. Symptoms include acute onset of decreased visual acuity or ocular pain and typically occur within hours to weeks of drug initiation. Untreated acute angle-closure glaucoma can lead to permanent vision loss. The primary treatment is to discontinue hydrochlorothiazide as rapidly as possible. Prompt medical or surgical treatments may need to be considered if the intraocular pressure remains uncontrolled. Risk factors for developing acute angle-closure glaucoma may include a history of sulfonamide or penicillin allergy.
Hypersensitivity reactions to hydrochlorothiazide may occur in patients with or without a history of allergy or bronchial asthma, but are more likely in patients with such a history.
Hydrochlorothiazide may alter glucose tolerance and raise serum levels of cholesterol and triglycerides.
Hydrochlorothiazide may raise the serum uric acid level due to reduced clearance of uric acid and may cause or exacerbate hyperuricemia and precipitate gout in susceptible patients.
Thiazides decrease urinary calcium excretion and may cause elevation of serum calcium. Avoid using candesartan cilexetil and hydrochlorothiazide tablets in patients with hypercalcemia.
Thiazide diuretics have been reported to cause exacerbation or activation of systemic lupus erythematosus.
Female patients of childbearing age should be told about the consequences of exposure to candesartan cilexetil and hydrochlorothiazide tablets during pregnancy. Discuss treatment options with women planning to become pregnant. Patients should be asked to report pregnancies to their physicians as soon as possible.
Tell patients receiving candesartan cilexetil and hydrochlorothiazide tablets that lightheadedness can occur, especially during the first days of therapy, and that it should be reported to the prescribing physician. Tell patients that if syncope occurs, discontinue candesartan cilexetil and hydrochlorothiazide tablets until the physician has been consulted.
Tell all patients that inadequate fluid intake, excessive perspiration, diarrhea, or vomiting can lead to an excessive fall in blood pressure, with the same consequences of lightheadedness and possible syncope
Tell patients receiving candesartan cilexetil and hydrochlorothiazide tablets not to use potassium supplements, salt substitutes containing potassium, or other drugs that may increase serum potassium levels without consulting the prescribing physician.
Because candesartan is not significantly metabolized by the cytochrome P450 system and at therapeutic concentrations has no effects on P450 enzymes, interactions with drugs that inhibit or are metabolized by those enzymes would not be expected.
Interactions common to both Candesartan Cilexetil and Hydrochlorothiazide
Non-Steroidal Anti-Inflammatory Agents including Selective Cyclooxygenase-2 Inhibitors (COX-2 Inhibitors) In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, co-administration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists, including candesartan, may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving candesartan and NSAID therapy.
The antihypertensive effect of angiotensin II receptor antagonists, including candesartan may be attenuated by NSAIDs including selective COX-2 inhibitors.
Lithium Increases in serum lithium concentrations and lithium toxicity have been reported during concomitant administration of lithium with angiotensin II receptor antagonists or hydrochlorothiazide. Monitor serum lithium levels during concomitant use.
Interactions with Candesartan Cilexetil
Dual Blockade of the Renin-Angiotensin System (RAS)
Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Closely monitor blood pressure, renal function and electrolytes in patients on candesartan cilexetil and hydrochlorothiazide tablets and other agents that affect the RAS.
Coadministration of cilexetil and hydrochlorothiazide tablets with potassium sparing diuretics, potassium supplements, potassium-containing salt substitutes or other drugs that raise serum potassium levels may result in hyperkalemia. Monitor serum potassium in such patients.
Do not co-administer aliskiren with candesartan cilexetil and hydrochlorothiazide tablets in patients with diabetes. Avoid use of aliskiren with candesartan cilexetil and hydrochlorothiazide tablets in patients with renal impairment (GFR <60 ml/min) (see CONTRAINDICATIONS).
Interactions with Hydrochlorothiazide
Alcohol, barbiturates, or narcotics − Potentiation of orthostatic hypotension may occur.
Antidiabetic drugs (oral agents and insulin) − Dosage adjustment of the antidiabetic drug may be required.
Diazoxide − the hyperglycemic effect of diazoxide may be enhanced by thiazides.
Ion Exchange resins − Single doses of either cholestyramine or colestipol resins bind the hydrochlorothiazide and reduce its absorption from the gastrointestinal tract by up to 85% and 43%, respectively. Stagger the dosage of hydrochlorothiazide and ion exchange resins such that hydrochlorothiazide is administered at least 4 hours before or 4-6 hours after the administration of resins.
Skeletal muscle relaxants, nondepolarizing (e.g., tubocurarine) − Possible increased responsiveness to muscle relaxants such as curare derivatives.
Digitalis − Thiazide-induced hypokalemia or hypomagnesemia may predispose to digoxin toxicity.
Noradrenaline − Thiazides may decrease arterial responsiveness to noradrenaline, but not enough to preclude effectiveness of the pressor agent for therapeutic use.
Steroids or Adrenocorticotropic Hormone − Hypokalemia may develop during concomitant use of steroids or adrenocorticotropic hormone (ACTH).
Cytotoxic products − Thiazides may reduce the renal excretion of cytotoxic medicinal products (e.g. cyclophosphamide, methotrexate) and potentiate their myelosuppressive effects.
Cyclosporine − Concomitant treatment with cyclosporine may increase the risk of hyperuricemia and gout-type complications.
No carcinogenicity studies have been conducted with the combination of candesartan cilexetil and hydrochlorothiazide. There was no evidence of carcinogenicity when candesartan cilexetil was orally administered to mice and rats for up to 104 weeks at doses up to 100 and 1000 mg/kg/day, respectively. Rats received the drug by gavage whereas mice received the drug by dietary administration. These (maximally-tolerated) doses of candesartan cilexetil provided systemic exposures to candesartan (AUCs) that were, in mice, approximately 7 times and, in rats, more than 70 times the exposure in man at the maximum recommended daily human dose (32 mg). Two-year feeding studies in mice and rats conducted under the auspices of the National Toxicology Program (NTP) uncovered no evidence of a carcinogenic potential of hydrochlorothiazide in female mice (at doses of up to approximately 600 mg/kg/day) or in male and female rats (at doses of up to approximately 100 mg/kg/day). The NTP, however, found equivocal evidence for hepatocarcinogenicity in male mice.
Candesartan cilexetil or candesartan (the active metabolite), in combination with hydrochlorothiazide, tested positive in vitro in the Chinese hamster lung (CHL) chromosomal aberration assay and mouse lymphoma mutagenicity assay. The candesartan cilexetil/hydrochlorothiazide combination tested negative for mutagenicity in bacteria (Ames test), for unscheduled DNA synthesis in rat liver, for chromosomal aberrations in rat bone marrow and for micronuclei in mouse bone marrow.
Both candesartan and its O-deethyl metabolite tested positive for genotoxicity in the in vitro CHL chromosomal aberration assay. Neither compound tested positive in the Ames microbial mutagenesis assay or in the in vitro mouse lymphoma cell assay. Candesartan (but not its O-deethyl metabolite) was also evaluated in vivo in the mouse micronucleus test and in vitro in the Chinese hamster ovary (CHO) gene mutation assay, in both cases with negative results. Candesartan cilexetil was evaluated in the Ames test, the in vitro mouse lymphoma cell assay, the in vivo rat hepatocyte unscheduled DNA synthesis assay and the in vivo mouse micronucleus test, in each case with negative results. Candesartan cilexetil was not evaluated in the CHL chromosomal aberration or CHO gene mutation assays.
When hydrochlorothiazide was tested alone, positive results were obtained in vitro in the CHO sister chromatid exchange (clastogenicity) and mouse lymphoma cell (mutagenicity) assays and in the Aspergillus nidulans non-disjuncition assay. Hydrochorothiazide was not genotoxic in vitro in the Ames test for point mutations and the CHO test for chromosomal aberrations, or in vivo in assays using mouse germinal cell chromosomes, Chinese hamster bone marrow chromosomes, and the Drosophila sex-linked recessive lethal trait gene.
No fertility studies have been conducted with the combination of candesartan cilexetil and hydrochlorothiazide. Fertility and reproductive performance were not affected in studies with male and female rats given oral doses of up to 300 mg candesartan cilexetil/kg/day (83 times the maximum daily human dose of 32 mg on a body surface area basis). Hydrochlorothiazide had no adverse effects on the fertility of mice and rats of either sex in studies wherein these species were exposed, via their diet, to doses of up to 100 and 4 mg/kg, respectively, prior to conception and throughout gestation.
It is not known whether candesartan is excreted in human milk, but candesartan has been shown to be present in rat milk. Thiazides appear in human milk. Because of the potential for adverse effects on the nursing infant, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.
Neonates with a history of in utero exposure to candesartan cilexetil and hydrochlorothiazide tablets:
If oliguria or hypotension occurs, direct attention toward support of blood pressure and renal perfusion. Exchange transfusions or dialysis may be required as a means of reversing hypotension and/or substituting for disordered renal function.
Safety and effectiveness in pediatric patients have not been established.
DrugInserts.com provides trustworthy package insert and label information about marketed drugs as submitted by manufacturers to the US Food and Drug Administration. Package information is not reviewed or updated separately by DrugInserts.com. Every individual package label entry contains a unique identifier which can be used to secure further details directly from the US National Institutes of Health and/or the FDA.