Hyzaar 50/12.5mg Tablets
Overview
What is this medicine?
How to Use This Medicine
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication as directed, with or without food. Continue taking it even if you feel well, as instructed by your doctor or healthcare provider.
Be aware that this medication may increase your urine production. To minimize sleep disturbances, try to avoid taking it close to bedtime. Unless your doctor advises you to limit fluid intake, drink plenty of non-caffeinated liquids.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep the lid tightly closed and store all medications in a safe location, out of reach of children and pets.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses.
Lifestyle & Tips
- Take the medication exactly as prescribed, usually once daily, with or without food.
- Do not stop taking the medication without consulting your doctor, even if you feel well.
- Continue to follow a low-sodium diet as recommended by your doctor or dietitian.
- Engage in regular physical activity as advised by your healthcare provider.
- Limit alcohol intake.
- Avoid potassium supplements or salt substitutes containing potassium unless directed by your doctor.
- Monitor your blood pressure regularly at home if advised by your doctor.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Condition-Specific Dosing:
Pediatric Dosing
Dose Adjustments
Renal Impairment:
Hepatic Impairment:
Pharmacology
Mechanism of Action
Pharmacokinetics
Absorption:
Distribution:
Elimination:
Pharmacodynamics
Safety & Warnings
BLACK BOX WARNING
Side Effects
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high blood sugar, including:
+ Confusion
+ Feeling sleepy
+ Unusual thirst or hunger
+ Passing urine more often
+ Flushing
+ Fast breathing
+ Breath that smells like fruit
Signs of kidney problems, such as:
+ Unable to pass urine
+ Change in how much urine is passed
+ Blood in the urine
+ Sudden weight gain
Signs of fluid and electrolyte problems, including:
+ Mood changes
+ Confusion
+ Muscle pain or weakness
+ Fast or abnormal heartbeat
+ Severe dizziness or passing out
+ Increased thirst
+ Seizures
+ Feeling very tired or weak
+ Decreased appetite
+ Unable to pass urine or change in the amount of urine produced
+ Dry mouth
+ Dry eyes
+ Severe upset stomach or vomiting
Signs of a pancreas problem (pancreatitis), such as:
+ Severe stomach pain
+ Severe back pain
+ Severe upset stomach or vomiting
Severe dizziness or passing out
Swelling in the arms or legs
Yellow skin or eyes
Difficulty getting or maintaining an erection
This medication can also cause eye problems, which may lead to permanent vision loss if left untreated. If you experience any of the following symptoms, contact your doctor right away:
Changes in vision
Eye pain
These symptoms usually occur within hours to weeks of starting the medication.
Rare but Serious Side Effects
Rarely, people taking hydrochlorothiazide have developed certain types of skin cancer. To minimize your risk, protect your skin from the sun and follow your doctor's instructions for skin checks. If you notice any changes in the color or size of a mole, or any new or changing skin lump or growth, contact your doctor immediately.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people do not experience any side effects or only have mild ones, some may be bothered by the following:
Dizziness
Signs of a common cold
Back pain
If you experience any of these side effects or any other symptoms that concern you, contact your doctor or seek medical attention.
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting (especially when standing up)
- Signs of electrolyte imbalance: unusual tiredness, muscle weakness, muscle cramps, nausea, vomiting, dry mouth, increased thirst, irregular heartbeat.
- Signs of kidney problems: little or no urination, swelling in your feet or ankles, feeling tired or short of breath.
- Signs of allergic reaction: rash, itching, swelling (especially of the face, tongue, or throat), severe dizziness, trouble breathing.
- Sudden decrease in vision or eye pain (may be signs of acute angle-closure glaucoma, rare but serious).
Before Using This Medicine
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
A known sulfa allergy.
Current use of dofetilide.
Inability to urinate.
Dehydration - discuss this condition with your doctor.
Concurrent use of a medication containing aliskiren, particularly if you have diabetes or kidney problems.
This list is not exhaustive, and it is crucial to disclose all your medications (prescription, over-the-counter, natural products, and vitamins) and health issues to your doctor and pharmacist. They will help determine the safety of taking this medication with your other drugs and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
Precautions & Cautions
To minimize the risk of dizziness or fainting, stand up slowly after sitting or lying down, and exercise caution when climbing stairs. If you have diabetes, closely monitor your blood sugar levels as directed by your healthcare provider. Additionally, check your blood pressure as instructed and undergo blood tests as recommended by your doctor.
Be aware that this medication may interfere with certain laboratory tests. Inform all your healthcare providers and laboratory personnel that you are taking this drug. If you are using a salt substitute containing potassium, a potassium-sparing diuretic, or a potassium product, consult with your doctor. Similarly, if you are on a low-sodium or sodium-free diet, discuss this with your doctor.
Before using over-the-counter (OTC) products that may increase blood pressure, such as cough or cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, or certain natural products, consult with your doctor. Also, discuss the use of alcohol, marijuana, or other forms of cannabis, as well as prescription or OTC medications that may cause drowsiness, with your doctor.
In hot weather or during physical activity, be cautious and drink plenty of fluids to prevent dehydration. If you experience excessive sweating, fluid loss, vomiting, or diarrhea, inform your doctor, as these conditions may lead to low blood pressure.
If you are taking cholestyramine or colestipol, consult with your pharmacist about the proper administration of these medications with this drug. Be aware of the potential for gout attacks. This medication may also cause elevated cholesterol and triglyceride levels; discuss this with your doctor.
If you have lupus, this medication may exacerbate your condition. Immediately inform your doctor if you experience any new or worsening symptoms. Individuals 65 years or older should use this medication with caution, as they may be more susceptible to side effects.
If you are breastfeeding, consult with your doctor to discuss any potential risks to your baby.
Overdose Information
Overdose Symptoms:
- Severe hypotension (low blood pressure)
- Tachycardia (fast heart rate)
- Bradycardia (slow heart rate)
- Electrolyte depletion (e.g., hypokalemia, hyponatremia)
- Dehydration
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Treatment is supportive and symptomatic, including intravenous fluids for hypotension and correction of electrolyte imbalances.
Drug Interactions
Contraindicated Interactions
- Aliskiren (in patients with diabetes or renal impairment)
- Concomitant use with ACE inhibitors (in patients with diabetic nephropathy)
Major Interactions
- Potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride)
- Potassium supplements
- Lithium
- NSAIDs (including COX-2 inhibitors)
- Other antihypertensive agents (additive effects)
- Corticosteroids, ACTH (enhanced electrolyte depletion with HCTZ)
- Digoxin (increased risk of toxicity with HCTZ-induced hypokalemia/hypomagnesemia)
Moderate Interactions
- Barbiturates, narcotics, alcohol (orthostatic hypotension)
- Antidiabetic agents (HCTZ may decrease glucose tolerance)
- Cholestyramine, colestipol resins (reduced HCTZ absorption)
- Pressor amines (e.g., norepinephrine, HCTZ may reduce response)
- Skeletal muscle relaxants, non-depolarizing (e.g., tubocurarine, HCTZ may potentiate effect)
- Allopurinol (increased risk of hypersensitivity reactions with HCTZ)
- Amantadine (increased risk of adverse effects with HCTZ)
- Cytotoxic agents (e.g., cyclophosphamide, methotrexate, HCTZ may reduce renal excretion)
- CYP2C9 inhibitors (e.g., fluconazole, amiodarone, may increase losartan and E-3174 levels)
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Rationale: To establish baseline and guide therapy.
Timing: Prior to initiation of therapy
Rationale: To assess baseline electrolyte status, as both components can affect levels.
Timing: Prior to initiation of therapy
Rationale: To assess baseline kidney function, as both components are renally cleared and can affect renal function.
Timing: Prior to initiation of therapy
Rationale: Losartan is metabolized by the liver; to assess baseline hepatic function.
Timing: Prior to initiation of therapy
Rationale: Hydrochlorothiazide can increase uric acid levels.
Timing: Prior to initiation of therapy
Rationale: Hydrochlorothiazide can affect glucose metabolism.
Timing: Prior to initiation of therapy
Routine Monitoring
Frequency: Regularly, e.g., weekly initially, then monthly or as clinically indicated
Target: <130/80 mmHg (or individualized target)
Action Threshold: If BP remains uncontrolled, consider dose adjustment or additional therapy. If hypotensive, consider dose reduction.
Frequency: Within 1-2 weeks of initiation/dose change, then periodically (e.g., every 3-6 months) or as clinically indicated.
Target: 3.5-5.0 mEq/L
Action Threshold: If <3.5 mEq/L (hypokalemia) or >5.5 mEq/L (hyperkalemia), investigate cause and manage appropriately (e.g., potassium supplementation/restriction, dose adjustment, discontinuation).
Frequency: Periodically (e.g., every 3-6 months) or as clinically indicated.
Target: 135-145 mEq/L
Action Threshold: If <130 mEq/L (hyponatremia), investigate and manage.
Frequency: Within 1-2 weeks of initiation/dose change, then periodically (e.g., every 3-6 months) or as clinically indicated.
Target: Stable within patient's baseline range
Action Threshold: If significant increase in creatinine (>30% from baseline) or decrease in eGFR, investigate and manage (e.g., dose adjustment, discontinuation, rule out renal artery stenosis).
Frequency: Periodically (e.g., annually) or if symptoms of gout develop.
Target: Within normal limits
Action Threshold: If elevated and symptomatic, consider management for hyperuricemia or alternative antihypertensive.
Frequency: Periodically (e.g., annually) or more frequently in diabetic patients.
Target: Within target range for patient
Action Threshold: If elevated, consider management for hyperglycemia or alternative antihypertensive.
Symptom Monitoring
- Dizziness
- Lightheadedness
- Fatigue
- Muscle cramps or weakness (signs of electrolyte imbalance)
- Dry mouth, thirst (signs of dehydration)
- Swelling of face, lips, tongue, or throat (angioedema - rare but serious)
- Persistent cough (less common with ARBs than ACEIs)
- Unusual bruising or bleeding (rare, due to thrombocytopenia with HCTZ)
- Yellowing of skin or eyes (jaundice - rare)
Special Patient Groups
Pregnancy
Contraindicated in pregnancy, especially during the second and third trimesters, due to the risk of fetal injury and death. Discontinue as soon as pregnancy is detected.
Trimester-Specific Risks:
Lactation
Not recommended during breastfeeding. Both losartan and hydrochlorothiazide are excreted in breast milk. Hydrochlorothiazide can also suppress lactation.
Pediatric Use
Safety and effectiveness have not been established in pediatric patients. Not recommended for use in children.
Geriatric Use
No overall differences in effectiveness or safety have been observed between elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out. Start with the lowest effective dose and monitor closely for adverse effects, especially hypotension and electrolyte imbalances.
Clinical Information
Clinical Pearls
- Hyzaar is a first-line combination therapy for hypertension, particularly useful when monotherapy is insufficient.
- The combination of an ARB and a thiazide diuretic provides complementary mechanisms of action, often leading to better blood pressure control and reduced side effects compared to higher doses of a single agent.
- Monitor serum potassium levels closely, especially at initiation and after dose changes, as losartan can cause hyperkalemia and hydrochlorothiazide can cause hypokalemia, leading to variable effects on potassium.
- Advise patients to report any signs of angioedema (swelling of face, lips, tongue, throat) immediately, although it is less common with ARBs than ACE inhibitors.
- Educate patients about the importance of hydration, especially during hot weather or exercise, to prevent dehydration and electrolyte imbalances due to the diuretic component.
- Avoid concomitant use with NSAIDs, as they can reduce the antihypertensive effect and increase the risk of renal dysfunction, especially in elderly or volume-depleted patients.
Alternative Therapies
- ACE Inhibitors (e.g., Lisinopril, Ramipril)
- Calcium Channel Blockers (e.g., Amlodipine, Nifedipine)
- Beta-Blockers (e.g., Metoprolol, Atenolol)
- Other Diuretics (e.g., Loop diuretics, Potassium-sparing diuretics)
- Direct Renin Inhibitors (e.g., Aliskiren - generally not recommended in combination with ARBs/ACEIs)