How does excess licorice consumption cause hypertension and hypokalemia?

The active ingredient of licorice, glycyrrhizic acid or glycyrrhizin, is first converted to glycyrrhetinic acid (GRA) in the bowel which is then absorbed. Once in the circulation, GRA inhibits activation of 11 β-hydroxysteroid dehydrogenase 2 (11 β-HSD2), an enzyme in renal tissue that converts active cortisol to inactive cortisone. Without the full action of this enzyme, proper sodium and potassium homeostasis would be difficult because cortisol is just as effective in stimulating mineralocorticoid receptors as aldosterone but with 100-1000 times higher concentration than that of aldosterone! 1-3

Other ways that GRA may cause hypertension and hypokalemia include inhibition of 5 β-reductase in the liver, an enzyme that metabolizes aldosterone and direct stimulation of mineralocorticoid receptors, though overall these mechanisms may not be as important as the effect of GRA on cortisol metabolism in renal tissue.1,2

Besides causing fluid retention, licorice ingestion has also been found to increase systemic vascular resistance possibly by increasing vascular tone and remodeling of the vascular wall, potentiating the vasoconstrictor actions of angiotensin II and catecholamines in smooth muscle, and suppressing vasodilatory systems, including endothelial nitric oxide synthase and prostacyclin synthesis.

It’s no wonder that the FDA issued a statement in 2017: “If you’re 40 or older, eating 2 ounces of black licorice a day for a day for at least two weeks could land you in the hospital with an irregular heart rhythm or arrhythmia.” 5

Bonus Pearl: Did you know that as early as 1951, extract of licorice was reported for treatment of Addison’s disease, a combination of licorice and soy sauce has been reported to be “life-saving” in a patient with Addison’s disease (2007), and GRA food supplementation may lower serum potassium in chronic hemodialysis patients (2009)? 6,7

 

References

  1. Sontia B, Mooney J, Gaudet L, et al. Pseudohyperaldosteronism, liquorice and hypertension. J Clin Hypertens (Greenwich) 2008; 10:153-57. https://www.ncbi.nlm.nih.gov/pubmed/18256580
  2. Omar HR, Komarova I, El-Ghonemi M, et al. Licorice abuse: time to send a warning message. The Adv Endocrinol Metab 2012;3:125-138. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498851/
  3. Penninkilampi R, Eslick EM, Eslick GD. The association between consistent licorice ingestion, hypertension and hypokalaemia: as systematic review and meta-analysis. Journal of Human Hypertension 2017;31:699-707. https://www.ncbi.nlm.nih.gov/pubmed/28660884
  4. Black licorice: trik or treat? https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm 277152.htm
  5. Hautaniemi EJ, Tahvanainen AM, Koskela JK, et al. Voluntary liquorice ingestion increases blood pressure via increased volume load, elevated peripheral arterial resistance, and decreased aortic compliance. Sci Rep 2017;7:10947. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5591274/
  6. Groen J, Pelser H, Willebrands AF, et al. Extract of licorice for the treatment of Addison’s disease. N Engl J Med 1951;244:471-75. https://www.ncbi.nlm.nih.gov/pubmed/14806786
  7. Cooper H, Bhattacharya B, Verma V, et al. Liquorice and soy sauce, a life-saving concoction in a patient with Addison’s disease. Ann Clin Biochem 2007;44:397-99. https://www.ncbi.nlm.nih.gov/pubmed/17594790
  8. Farese S, Kruse Anja, Pasch A, et al. Glycyrrhetinic acid food supplementation lowers serum potassium concentration in chronic hemodialysis patients. Kidney International 2009;76:877-84. https://www.ncbi.nlm.nih.gov/pubmed/19641483
How does excess licorice consumption cause hypertension and hypokalemia?

Should my patient with compensated heart failure be placed on a sodium-restricted diet?

Although sodium restriction is routinely recommended for patients with heart failure (HF), the data is often conflicting with a number of studies even suggesting that it may be harmful in some patients.

Two randomized trials (by the same group) involving patients with compensated HF recently discharged from the hospital reported that “less restricted” sodium diet (2.8 gm/d) along with fluid restriction (1 L/day) and high dose furosemide (at least 125-250 mg furosemide twice daily) was associated with less rates of readmissions and improved levels of brain natriuretic peptide, aldosterone and plasma renin activity compared to patients on more restricted sodium diet (1.8 gm/d). 1,2

Analysis of data from the multihospital HF Adherence and Retention Trial enrolling New York Heart Association functional class II/III HF patients found that sodium restriction (<2.5 gm/d) was associated with significantly higher risk of death or HF hospitalization but only in patients not on an angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB). 3

In normal subjects who are not sodium deprived, excess sodium intake has been shown to cause expansion of intravascular volume without increasing total body water. 4 Thus, sodium restriction combined with diuretics may reduce intravascular volume and renal perfusion, further stimulating the renin-angiotensin-aldosterone system and fluid retention. 5

Bonus Pearl: Did you know that the 2013 American College of Cardiology Foundation/American Heart Association guidelines downgraded the recommendation for sodium restriction to Class IIa (reasonable) with Level of Evidence:C? 6

References

  1. Paterna S, Gaspare P, Fasullo S, et al. Normal-sodium diet compared with low-sodium diet in compensated congestive heart failure: is sodium an old enemy or a new friend? Clin Sci 2008;114:221-230. https://www.ncbi.nlm.nih.gov/pubmed/17688420
  2. Paterna S, Parrinello G, Cannizzaro S, et al. Medium term effects of different dosage of diuretic, sodium, and fluid administration on neurohormonal and clinical outcome in patients with recently compensated heart failure. Am J Cardiol 2009;103:93-102. https://www.ncbi.nlm.nih.gov/pubmed/19101237
  3. Doukky R, Avery E, Mangla A, et al.Impact of dietary sodium restriction on heart failure outcomes. J Am Coll Cariol HF 2016;4:24-35. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4705447/
  4. Heer M, Baisch F, Kropp J et al. High dietary sodium chloride consumption may not induce body fluid retention in humans. Am J Physiol Renal Physiol 2000;278:F585-F595. https://www.ncbi.nlm.nih.gov/pubmed/10751219
  5. Rothberg MB, Sivalingam SK. The new heart failure diet: less salt restriction, more micronutrients. J Gen Intern Med 25;1136-7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2955483/
  6. Yancy CW, Jessup M, Bozkurt B, et al. 2013 CCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2013;62:e147-239. https://www.ncbi.nlm.nih.gov/pubmed/23741058

If you liked this pearl, sign up under menu and receive future pearls straight into your mailbox!

Should my patient with compensated heart failure be placed on a sodium-restricted diet?

The serum creatinine of my patient originally admitted for management of tense ascites is slowly rising. How concerned should I be?

Although the causes of increasing serum creatinine (SCr) in patients with cirrhosis are legion (eg, sepsis, acute tubular injury, and intravascular volume depletion due to over-diuresis, gastrointestinal bleed, or other causes), the most feared cause is often hepatorenal syndrome (HRS). HRS is a functional renal impairment that reflects the final pathophysiological stages of systemic circulatory impairment1, and significantly contributes to a worsening prognosis in patients with cirrhosis2. For example, without treatment, in patients whose SCr doubles in less than 2 weeks (type I HRS) the median survival is less than 2 weeks , while in those who develop a more gradual renal impairment (type II HRS) the median survival is 6 months3.

Physiologically, HRS is a culmination of significant vasodilation in the splanchnic arteries which, in time, leads to reduced organ perfusion due to a drop in the cardiac output. The associated increase in the activity of the renin-angiotensin-aldosterone and the sympathetic nervous systems contributes to sodium and water retention, and further exacerbates intra-renal vasoconstriction and ascites3.

The primary goal in the medical management of HRS is to increase splanchnic vascular resistance4, often by administering a combination of IV albumin, octreotide and other vasoconstricting agents (eg, midodrine, norepinephrine, or terlipressin [unavailable in US and Canada]).  Of interest, in addition to expanding the circulating plasma volume, albumin may have a vasoconstricting effect by binding to endotoxins, nitric oxide, bilirubin and fatty acids4!

 

References

  1. Arroyo V, Fernandez J, Gines P. Pathogenesis and treatment of hepatorenal syndrome. Semin Liver Dis 2008;28:81-95.
  2. Salerno F, Gerbes A, Ginès P, et al. Diagnosis, prevention and treatment of hepatorenal syndrome in cirrhosis. Gut. 2007 Sep;56(9):1310-8.
  3. Cardenas A, Gines P. A Patient with cirrhosis and increasing creatinine Level: What Is It and what to do? Clin Gatroenterol Hepatol 2009;7:1287–1291. 
  4. Baraldi O, Valentini C, Donati G, et al. Hepatorenal syndrome: Update on diagnosis and treatment. World J Nephrol. 2015;4:511-20.

Contributed by Alireza Sameie, Medical Student, Harvard Medical School

The serum creatinine of my patient originally admitted for management of tense ascites is slowly rising. How concerned should I be?