Usage
- This combination drug is prescribed for the treatment of hypertension (high blood pressure) when monotherapy (treatment with a single drug) is insufficient to control blood pressure. It may also indirectly lower the risks of heart attack and stroke in individuals at risk.
- Pharmacological Classification: Antihypertensive (a combination of a calcium channel blocker, an angiotensin II receptor blocker, and a thiazide diuretic).
- Mechanism of Action: This triple-combination therapy targets multiple pathways involved in blood pressure regulation. Amlodipine blocks calcium channels in vascular smooth muscle, leading to vasodilation. Telmisartan blocks angiotensin II receptors, preventing vasoconstriction and aldosterone release. Hydrochlorothiazide increases urine output by inhibiting sodium and chloride reabsorption in the kidneys, further reducing blood volume and pressure.
Alternate Names
- This combination does not have a universally recognized international nonproprietary name (INN). It is often referred to by the names of its components.
- Brand Names: Examples of Brand names include but are not limited to: Wotel-AMH, Telsite AMH.
How It Works
- Pharmacodynamics: The combined effect of the three drugs leads to a synergistic reduction in blood pressure by targeting different mechanisms: vasodilation, reduction of blood volume, and inhibition of the renin-angiotensin-aldosterone system.
- Pharmacokinetics:
- Absorption: Amlodipine is well-absorbed orally, telmisartan is incompletely absorbed, and hydrochlorothiazide is readily absorbed from the gastrointestinal tract.
- Metabolism: Amlodipine is extensively metabolized by the liver, telmisartan is primarily excreted unchanged in bile, and hydrochlorothiazide is not extensively metabolized.
- Elimination: Amlodipine is excreted in urine and feces, telmisartan primarily in feces, and hydrochlorothiazide primarily in urine.
- Mode of Action:
- Amlodipine: Inhibits calcium influx into vascular smooth muscle and cardiac muscle, reducing muscle contraction and promoting vasodilation.
- Telmisartan: Blocks the binding of angiotensin II to its receptors, inhibiting vasoconstriction and aldosterone release.
- Hydrochlorothiazide: Inhibits sodium chloride cotransporter in the distal convoluted tubule of the kidney, increasing sodium and water excretion.
- Receptor Binding/Enzyme Inhibition/Neurotransmitter Modulation:
- Telmisartan: Angiotensin II receptor blocker (ARB).
- Amlodipine: Calcium channel blocker.
- Hydrochlorothiazide: Inhibition of sodium-chloride symporter.
- Elimination Pathways:
- Amlodipine: Hepatic metabolism, renal and fecal excretion.
- Telmisartan: Primarily biliary excretion.
- Hydrochlorothiazide: Renal excretion.
Dosage
Standard Dosage
Adults:
- The typical starting dose is often one tablet containing amlodipine 5 mg, telmisartan 40 mg, and hydrochlorothiazide 12.5 mg, taken orally once daily. The dose may be adjusted by the physician as needed up to a maximum dose of amlodipine 10 mg, telmisartan 80 mg, and hydrochlorothiazide 25 mg per day. It is best to avoid bedtime doses if increased urination becomes bothersome.
Children:
- The safety and efficacy of this combination have not been established in the pediatric population. Use and dose must be determined by a doctor on a case-by-case basis.
Special Cases:
- Elderly Patients: Start with a lower dose and titrate cautiously, monitoring for side effects.
- Patients with Renal Impairment: Dose adjustment may be necessary for severe renal impairment. Patients on hemodialysis are more susceptible to hypotension and require close monitoring.
- Patients with Hepatic Dysfunction: Start with a lower dose and titrate slowly. Biliary obstruction or hepatic insufficiency can reduce clearance, requiring closer monitoring.
- Patients with Comorbid Conditions: Careful consideration is necessary for patients with diabetes, cardiovascular disease, or other conditions, as dose adjustments or closer monitoring may be required.
Clinical Use Cases
- The specific use cases listed (intubation, surgical procedures, mechanical ventilation, ICU use, emergency situations) are not standard indications for this drug combination. Its primary use is for long-term management of hypertension.
Dosage Adjustments
- Dose adjustments are based on patient-specific factors such as renal function, hepatic function, concomitant medications, and response to therapy.
Side Effects
Common Side Effects
- Dizziness, headache, fatigue, peripheral edema (swelling in the hands or feet), electrolyte disturbances (such as hypokalemia), increased urination, dehydration, flushing, back pain, nausea, diarrhea, and stomach pain.
Rare but Serious Side Effects
- Angioedema (swelling of face, lips, tongue, or throat), hypotension, syncope, acute renal failure, hyperkalemia, and hepatotoxicity.
Long-Term Effects
- Electrolyte imbalances, renal dysfunction, and cardiovascular events if hypertension is not adequately controlled.
Adverse Drug Reactions (ADR)
- Any severe or persistent side effects should be reported to a healthcare professional immediately.
Contraindications
- Hypersensitivity to any component of the drug, pregnancy (especially second and third trimesters), anuria, bilateral renal artery stenosis, and concomitant use of aliskiren in patients with diabetes.
Drug Interactions
- Lithium, digoxin, metformin, sildenafil, simvastatin, ACE inhibitors (e.g., enalapril, lisinopril), immunosuppressants (e.g., cyclosporine), other antihypertensives (e.g., aliskiren), NSAIDs, potassium supplements, and grapefruit juice.
- CYP450 interactions: Amlodipine is metabolized by CYP3A4. Concomitant use of CYP3A4 inhibitors or inducers may necessitate dose adjustments.
Pregnancy and Breastfeeding
- Pregnancy Safety Category: D (contraindicated in the second and third trimesters). This combination can cause fetal harm when administered during pregnancy and should be discontinued as soon as pregnancy is detected.
- Breastfeeding: Not recommended. The drug is excreted in breast milk and may cause adverse effects in infants.
Drug Profile Summary
- Mechanism of Action: Combination of calcium channel blocker, ARB, and thiazide diuretic leading to vasodilation, reduced blood volume, and inhibition of the renin-angiotensin-aldosterone system.
- Side Effects: Dizziness, headache, fatigue, peripheral edema, electrolyte disturbances, increased urination.
- Contraindications: Hypersensitivity, pregnancy, anuria, bilateral renal artery stenosis, concomitant use of aliskiren in patients with diabetes.
- Drug Interactions: Lithium, digoxin, ACE inhibitors, potassium supplements, grapefruit juice.
- Pregnancy & Breastfeeding: Contraindicated in pregnancy, not recommended during breastfeeding.
- Dosage: Typically starts with amlodipine 5 mg/telmisartan 40 mg/hydrochlorothiazide 12.5 mg once daily, adjustable as needed.
- Monitoring Parameters: Blood pressure, serum electrolytes (especially potassium), renal function (BUN, creatinine).
Popular Combinations
- While this medication itself is a triple combination, it may be prescribed alongside other medications like statins for cholesterol control or other antihypertensives if blood pressure remains uncontrolled.
Precautions
- General Precautions: Assess renal and hepatic function, electrolyte levels, and monitor blood pressure regularly.
- Specific Populations: See Dosage/Special Cases.
- Lifestyle Considerations: Encourage lifestyle modifications, including a low-sodium diet, regular exercise, and weight management. Limit alcohol intake. Avoid driving or operating machinery until you know how this medication affects you.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Amlodipine + Hydrochlorothiazide + Telmisartan?
A: The typical starting dose is amlodipine 5 mg/telmisartan 40 mg/hydrochlorothiazide 12.5 mg once daily. The dose may be adjusted based on individual patient needs and response to therapy up to a maximum of amlodipine 10 mg/telmisartan 80 mg/hydrochlorothiazide 25 mg.
Q2: What are the most common side effects?
A: Dizziness, headache, fatigue, peripheral edema, and electrolyte imbalances.
Q3: Can this combination be used in patients with renal impairment?
A: Use with caution. Dose adjustments may be necessary, and patients on hemodialysis require careful monitoring.
Q4: Is this drug safe during pregnancy?
A: No. It is contraindicated during the second and third trimesters of pregnancy due to the risk of fetal harm.
Q5: What are the major drug interactions to be aware of?
A: Interactions can occur with lithium, digoxin, ACE inhibitors, potassium supplements, and grapefruit juice, among others.
Q6: How does this drug compare to monotherapy for hypertension?
A: This combination is typically used when monotherapy is inadequate to control blood pressure. It offers a synergistic effect by targeting multiple pathways.
Q7: What monitoring parameters are essential for patients taking this combination?
A: Blood pressure, serum electrolytes (particularly potassium), renal function (BUN, creatinine).
Q8: What should patients be advised regarding lifestyle modifications?
A: Adopt a low-sodium diet, engage in regular exercise, manage weight, and limit alcohol consumption.
Q9: Can this combination be crushed or chewed?
A: Some formulations may be available that can be crushed, but it is essential to consult the specific product information before altering the dosage form.
Q10: What should I do if a patient misses a dose?
A: Take the missed dose as soon as remembered unless it is close to the next scheduled dose. Do not double the dose.
