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Drug Interactions between hydrochlorothiazide / quinapril and levothyroxine

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

hydroCHLOROthiazide quinapril

Applies to: hydrochlorothiazide / quinapril and hydrochlorothiazide / quinapril

MONITOR: Although they are frequently combined in clinical practice, diuretics and angiotensin converting enzyme (ACE) inhibitors may have additive effects. Coadministration makes hypotension and hypovolemia more likely than does either drug alone. Some ACE inhibitors may attenuate the increase in the urinary excretion of sodium caused by some loop diuretics. Some patients on diuretics, especially those on dialysis or a dietary salt restriction, may experience acute hypotension with lightheadedness and dizziness after receiving the first dose of the ACE inhibitor. In addition, ACE inhibitors may cause renal insufficiency or acute renal failure in patients with sodium depletion or renal artery stenosis.

MANAGEMENT: Monitoring of blood pressure, diuresis, electrolytes, and renal function is recommended during coadministration. The possibility of first-dose hypotensive effects may be minimized by initiating therapy with small doses of the ACE inhibitor, or either discontinuing the diuretic temporarily or increasing the salt intake approximately one week prior to initiating an ACE inhibitor. Alternatively, the patient may remain under medical supervision for at least two hours after the first dose of the ACE inhibitor, or until blood pressure has stabilized.

References

  1. Reader C, Peyregne EA, Suarez LD (1983) "Amrinone therapy in congestive cardiomyopathy." Am Heart J, 105, p. 1045
  2. Fujimura A, Shimokawa Y, Ebihara A (1990) "Influence of captopril on urinary excretion of furosemide in hypertensive subjects." J Clin Pharmacol, 30, p. 538-42
  3. Funck-Brentano C, Chatellier G, Alexandre JM (1986) "Reversible renal failure after combined treatment with enalapril and furosemide in a patient with congestive heart failure." Br Heart J, 55, p. 596-8
  4. Weisser K, Schloos J, Jakob S, et al. (1992) "The influence of hydrochlorothiazide on the pharmacokinetics of enalapril in elderly patients." Eur J Clin Pharmacol, 43, p. 173-7
  5. Motwani JG, Fenwick MK, Morton JJ, Struthers AD (1992) "Furosemide-induced natriuresis is augmented by ultra-low-dose captopril but not by standard doses of captopril in chronic heart failure." Circulation, 86, p. 439-45
  6. Burnakis TG, Mioduch HJ (1984) "Combined therapy with captopril and potassium supplementation: a potential for hyperkalemia." Arch Intern Med, 144, p. 2371-2
  7. Murphy BF, Whitworth JA, Kincaid-Smith P (1984) "Renal insufficiency with combinations of angiotensin converting enzyme inhibitors and diuretics." Br Med J, 288, p. 844-5
  8. Thind GS (1985) "Renal insufficiency during angiotensin-converting enzyme inhibitor therapy in hypertensive patients with no renal artery stenosis." J Clin Hypertens, 1, p. 337-43
  9. Radley AS, Fitzpatrick RW (1987) "An evaluation of the potential interaction between enalapril and amiloride." J Clin Pharm Ther, 12, p. 319-23
  10. Champ JD (1993) "Case report: azotemia secondary to enalapril and diuretic use and the diagnosis of renovascular hypertension." Am J Med Sci, 305, p. 25-7
  11. Hume AL, Murphy JL, Lauerman SE (1989) "Angiotensin-converting enzyme inhibitor-induced cough." Pharmacotherapy, 9, p. 88-90
  12. Lee HB, Blaufox MD (1992) "Renal functional response to captopril during diuretic therapy." J Nucl Med, 33, p. 739-43
  13. DeQuattro V (1991) "Comparison of benazepril and other antihypertensive agents alone and in combination with the diuretic hydrochlorothiazide." Clin Cardiol, 14, iv28-32;
  14. (2002) "Product Information. Vasotec (enalapril)." Merck & Co., Inc
  15. McLay JS, McMurray JJ, Bridges AB, Fraser CG, Struthers AD (1993) "Acute effects of captopril on the renal actions of furosemide in patients with chronic heart failure." Am Heart J, 126, p. 879-86
  16. Sudoh T, Fujimura A, Shiga T, et al. (1993) "Influence of lisinopril on urinary electrolytes excretion after furosemide in healthy subjects." J Clin Pharmacol, 33, p. 640-3
  17. Lederle RM (1985) "Captopril and hydrochlorothiazide in the fixed combination multicenter trial." J Cardiovasc Pharmacol, 7, S63-9
  18. (2001) "Product Information. Aceon (perindopril)." Solvay Pharmaceuticals Inc
  19. Good JM, Brady AJ, Noormohamed FH, Oakley CM, Cleland JG (1994) "Effect of intense angiotensin II suppression on the diuretic response to furosemide during chronic ACE inhibition." Circulation, 90, p. 220-4
  20. (2001) "Product Information. Capoten (captopril)." Bristol-Myers Squibb
  21. (2001) "Product Information. Lexxel (enalapril-felodipine)." Astra-Zeneca Pharmaceuticals
  22. "Product Information. Zestril (lisinopril)." Astra-Zeneca Pharmaceuticals
  23. Cerner Multum, Inc. "Australian Product Information."
View all 23 references

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Moderate

levothyroxine quinapril

Applies to: levothyroxine and hydrochlorothiazide / quinapril

ADJUST DOSING INTERVAL: Administration of quinapril with some oral medications may significantly decrease their absorption and may result in subtherapeutic serum concentrations. The proposed mechanism is chelation of the drug by the magnesium hydroxide excipient in quinapril tablets.

MANAGEMENT: The manufacturer does not make a specific recommendation, but generally the administration of these drugs and magnesium-containing products should be separated by at least two to three hours.

References

  1. "Multum Information Services, Inc. Expert Review Panel"
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics."

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Drug and food interactions

Moderate

levothyroxine food

Applies to: levothyroxine

ADJUST DOSING INTERVAL: Consumption of certain foods as well as the timing of meals relative to dosing may affect the oral absorption of T4 thyroid hormone (i.e., levothyroxine). T4 oral absorption is increased by fasting and decreased by foods such as soybean flour (e.g., infant formula), cotton seed meal, walnuts, dietary fiber, calcium, and calcium fortified juices. Grapefruit or grapefruit products may delay the absorption of T4 thyroid hormone and reduce its bioavailability. The mechanism of this interaction is not fully understood.

MANAGEMENT: Some manufacturers recommend administering oral T4 as a single daily dose, on an empty stomach, one-half to one hour before breakfast. In general, oral preparations containing T4 thyroid hormone should be administered on a consistent schedule with regard to time of day and relation to meals to avoid large fluctuations in serum levels. Foods that may affect T4 absorption should be avoided within several hours of dosing if possible. Consult local guidelines for the administration of T4 in patients receiving enteral feeding.

References

  1. (2002) "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical
  2. (2022) "Product Information. Armour Thyroid (thyroid desiccated)." Forest Pharmaceuticals
  3. Wohlt PD, Zheng L, Gunderson S, Balzar SA, Johnson BD, Fish JT (2009) "Recommendations for the use of medications with continuous enteral nutrition." Am J Health Syst Pharm, 66, p. 1438-67

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Moderate

quinapril food

Applies to: hydrochlorothiazide / quinapril

GENERALLY AVOID: Moderate-to-high dietary intake of potassium can cause hyperkalemia in some patients who are using angiotensin converting enzyme (ACE) inhibitors. In some cases, affected patients were using a potassium-rich salt substitute. ACE inhibitors can promote hyperkalemia through inhibition of the renin-aldosterone-angiotensin (RAA) system.

MANAGEMENT: It is recommended that patients who are taking ACE inhibitors be advised to avoid moderately high or high potassium dietary intake. Particular attention should be paid to the potassium content of salt substitutes.

References

  1. (2002) "Product Information. Vasotec (enalapril)." Merck & Co., Inc
  2. Good CB, McDermott L (1995) "Diet and serum potassium in patients on ACE inhibitors." JAMA, 274, p. 538
  3. Ray K, Dorman S, Watson R (1999) "Severe hyperkalaemia due to the concomitant use of salt substitutes and ACE inhibitors in hypertension: a potentially life threatening interaction." J Hum Hypertens, 13, p. 717-20

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Moderate

hydroCHLOROthiazide food

Applies to: hydrochlorothiazide / quinapril

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.

References

  1. Sternbach H (1991) "Fluoxetine-associated potentiation of calcium-channel blockers." J Clin Psychopharmacol, 11, p. 390-1
  2. Shook TL, Kirshenbaum JM, Hundley RF, Shorey JM, Lamas GA (1984) "Ethanol intoxication complicating intravenous nitroglycerin therapy." Ann Intern Med, 101, p. 498-9
  3. Feder R (1991) "Bradycardia and syncope induced by fluoxetine." J Clin Psychiatry, 52, p. 139
  4. Ellison JM, Milofsky JE, Ely E (1990) "Fluoxetine-induced bradycardia and syncope in two patients." J Clin Psychiatry, 51, p. 385-6
  5. Rodriguez de la Torre B, Dreher J, Malevany I, et al. (2001) "Serum levels and cardiovascular effects of tricyclic antidepressants and selective serotonin reuptake inhibitors in depressed patients." Ther Drug Monit, 23, p. 435-40
  6. Cerner Multum, Inc. "Australian Product Information."
  7. Pacher P, Kecskemeti V (2004) "Cardiovascular side effects of new antidepressants and antipsychotics: new drugs, old concerns?" Curr Pharm Des, 10, p. 2463-75
  8. Andrews C, Pinner G (1998) "Postural hypotension induced by paroxetine." BMJ, 316, p. 595
View all 8 references

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Moderate

quinapril food

Applies to: hydrochlorothiazide / quinapril

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.

References

  1. Sternbach H (1991) "Fluoxetine-associated potentiation of calcium-channel blockers." J Clin Psychopharmacol, 11, p. 390-1
  2. Shook TL, Kirshenbaum JM, Hundley RF, Shorey JM, Lamas GA (1984) "Ethanol intoxication complicating intravenous nitroglycerin therapy." Ann Intern Med, 101, p. 498-9
  3. Feder R (1991) "Bradycardia and syncope induced by fluoxetine." J Clin Psychiatry, 52, p. 139
  4. Ellison JM, Milofsky JE, Ely E (1990) "Fluoxetine-induced bradycardia and syncope in two patients." J Clin Psychiatry, 51, p. 385-6
  5. Rodriguez de la Torre B, Dreher J, Malevany I, et al. (2001) "Serum levels and cardiovascular effects of tricyclic antidepressants and selective serotonin reuptake inhibitors in depressed patients." Ther Drug Monit, 23, p. 435-40
  6. Cerner Multum, Inc. "Australian Product Information."
  7. Pacher P, Kecskemeti V (2004) "Cardiovascular side effects of new antidepressants and antipsychotics: new drugs, old concerns?" Curr Pharm Des, 10, p. 2463-75
  8. Andrews C, Pinner G (1998) "Postural hypotension induced by paroxetine." BMJ, 316, p. 595
View all 8 references

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Moderate

levothyroxine food

Applies to: levothyroxine

ADJUST DOSING INTERVAL: Concurrent administration of calcium-containing products may decrease the oral bioavailability of levothyroxine by one-third in some patients. Pharmacologic effects of levothyroxine may be reduced. The exact mechanism of interaction is unknown but may involve nonspecific adsorption of levothyroxine to calcium at acidic pH levels, resulting in an insoluble complex that is poorly absorbed from the gastrointestinal tract. In one study, 20 patients with hypothyroidism who were taking a stable long-term regimen of levothyroxine demonstrated modest but significant decreases in mean free and total thyroxine (T4) levels as well as a corresponding increase in mean thyrotropin (thyroid-stimulating hormone, or TSH) level following the addition of calcium carbonate (1200 mg/day of elemental calcium) for 3 months. Four patients had serum TSH levels that were higher than the normal range. Both T4 and TSH levels returned to near-baseline 2 months after discontinuation of calcium, which further supported the likelihood of an interaction. In addition, there have been case reports suggesting decreased efficacy of levothyroxine during calcium coadministration. It is not known whether this interaction occurs with other thyroid hormone preparations.

MANAGEMENT: Some experts recommend separating the times of administration of levothyroxine and calcium-containing preparations by at least 4 hours. Monitoring of serum TSH levels is recommended. Patients with gastrointestinal or malabsorption disorders may be at a greater risk of developing clinical or subclinical hypothyroidism due to this interaction.

References

  1. Schneyer CR (1998) "Calcium carbonate and reduction of levothyroxine efficacy." JAMA, 279, p. 750
  2. Singh N, Singh PN, Hershman JM (2000) "Effect of calcium carbonate on the absorption of levothyroxine." JAMA, 283, p. 2822-5
  3. Csako G, McGriff NJ, Rotman-Pikielny P, Sarlis NJ, Pucino F (2001) "Exaggerated levothyroxine malabsorption due to calcium carbonate supplementation in gastrointestinal disorders." Ann Pharmacother, 35, p. 1578-83
  4. Neafsey PJ (2004) "Levothyroxine and calcium interaction: timing is everything." Home Healthc Nurse, 22, p. 338-9
View all 4 references

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

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Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

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