FDA’s warning against

“LIU BIAN LI”

Dr. P.Naina MohamedPharmacologist

Introduction• On 2nd June 2014, The Food and Drug

Administration (FDA) is advising consumers not to purchase or use “Liu Bian Li”.

• “Liu Bian Li” is promoted and sold for sexual enhancement on various websites and in some retail stores.

•  FDA laboratory analysis confirmed that “Liu Bian Li” contains Sildenafil.

• Sildenafil is a Phosphodiesterase 5 (PDE 5) inhibitor and is approved for the treatment of Erectile Dysfunction (ED).

Possible Mechanism of Action

“Liu Bian Li”

Undeclared Sildenafil

Inhibition of Phosphodiesterase 5 (PDE 5)

Inhibition of Breakdown of cGMP

Increase the concentration of cGMP in smooth muscle of corpus cavernosum and penile

arteries

Smooth muscle relaxation

Increase the blood flow to corpus cavernosum

Penile Erection

Interaction with Nitrates

“Liu Bian Li”

Undeclared Sildenafil

Interact with prescription drugs like nitrates (Nitroglycerin)

Excessive dilation of smooth muscle of blood vessels

Potentiation of Hypotensive effects

Blood pressure reduced to dangerous levels

Contraindicated

Interaction with Protease Inhibitors (Antiretrovirals)

“Liu Bian Li”

Undeclared Sildenafil

Interact with Protease Inhibitors like Saquinavir, Ritonavir, Indinavir, Nelfinavir, Amprenavir,

Fosamprenavir, Lopinavir, Atazanavir, , Tipranavir and Darunavir

Protease Inhibitors block CYP3A4-mediated sildenafil metabolism

Increased plasma levels of sildenafil

Increased risk of sildenafil adverse effects (hypotension, visual changes, priapism)

Contraindicated

Interaction with CYP3A4 Inhbitors

“Liu Bian Li”

Undeclared Sildenafil

Interact with CYP3A4 Inhibitors like Macrolide antibiotics (Telithromycin, Erythromycin,

Clarithromycin) and Antifungals (Voriconazole, Itraconazole, Ketoconazole)

CYP3A4 Inhibitors block CYP3A4-mediated sildenafil metabolism

Increased plasma levels of sildenafil

Increased risk of sildenafil adverse effects (hypotension, visual changes, priapism)

Conclusion FDA warns the Consumers should stop using this product

immediately and throw it away.  FDA advises the Consumers who have experienced any

negative side effects should consult a health care professional as soon as possible. 

FDA announces to the public of a growing trend of dietary supplements or conventional foods with hidden drugs and chemicals.  These products are typically promoted for sexual enhancement, weight loss, and body building, and are often represented as being “all natural.” 

FDA claims that they are unable to test and identify all products marketed as dietary supplements on the market that have potentially harmful hidden ingredients. 

FDA advises the Consumers to exercise caution before purchasing any product in the above categories.

References• http://

www.fda.gov/Drugs/ResourcesForYou/Consumers/BuyingUsingMedicineSafely/MedicationHealthFraud/ucm399597.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery

• Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e Laurence L. Brunton, Bruce A. Chabner, Björn C. Knollmann

• Harrison's Online Featuring the complete contents of Harrison's Principles ofInternal Medicine, 18e Dan L. Longo, Anthony S. Fauci, Dennis L. Kasper, Stephen L. Hauser, J. Larry Jameson, Joseph Loscalzo, Eds.

• Hurst's The Heart, 13eValentin Fuster, Richard A. Walsh, Robert A. Harrington

• Basic & Clinical Pharmacology, 12e Bertram G. Katzung, Susan B. Masters, Anthony J. Trevor

• Clinician's Pocket Reference, 11eLeonard G. Gomella, Steven A. Haist

References• http://www.micromedexsolutions.

com• http

://www.nlm.nih.gov/medlineplus/druginfo/meds/a699015.html

• http://www.rxlist.com/viagra-drug/clinical-pharmacology.htm

• http://www.medicinenet.com/sildenafil/article.htm

• http://www.pfizer.com/files/products/uspi_viagra.pdf