Place in therapy
The role of oral zinc sulfate in the treatment of viral warts can be summarized as unknown. Natural Standard database concluded that there is unclear scientific evidence for use of oral zinc sulfate in treatment of viral warts. 1 As if often the case with natural health products there are no clear definitive guidelines for when oral zinc sulfate therapy would be most effective or appropriate. There is clearly not enough evidence to recommend oral zinc sulfate therapy as a first line treatment option and probably even as a second or third line treatment option.
The most promising evidence regarding oral zinc sulfate use in viral wart treatment has been in patients suffering from multiple warts, for lengthy periods of time, and who have previously failed other treatment options. 2-4 There is one well designed study that failed to find any difference between treatment with placebo and treatment with oral zinc sulfate, however the primary endpoint failed to reach statistical significance.5 At the point in time where a patient is still suffering from multiple wart lesions and is running out of treatment options, oral zinc sulfate may present a reasonable option. The studied dose of oral zinc sulfate is most commonly 10mg/kg/day to a maximum of 600mg/day for 2 months. 2-4 There is also a potential that patients with low serum zinc levels may be more likely to respond to treatment however this has yet to be clearly demonstrated.3 It is also important to note that highly varying populations have studied the effect of oral zinc sulfate on the treatment of viral warts and found different results; this suggests that a population-specific demographic, such as diet, may play a role in response to oral zinc sulfate therapy. 2-5 A systematic review evaluating the efficacy of oral zinc sulfate in the treatment of viral warts found a favourable cure rate of 64% that reached statistical significance and had an odds ratio of 17; however the review noted the poor quality of data may affect these overall results. 6
Adverse events reported are consistently of gastrointestinal nature and usually include nausea, vomiting, and epigastric pain. 2-5 Adverse events were lower in one study that gave the total dose of zinc in three divided dose with the express purpose of decreasing gastrointestinal side effects and reported subsequent lower rates of gastrointestinal upset. 3
References
1. Natural Standard. [Internet]. Professional Monograph. [Updated June 2012; cited on June 26, 2012. Zinc. Available at http://www.naturalstandard.com/databases/herbssupplements/all/zinc.asp.
2. Mun S, Kim S, Jung D, et al. Oral zinc sulfate treatment for viral warts: An open-label study. J Dermatolog. 2011;38(6):541–5.
3. Al-Gurairi FT, Al-Waiz M, Sharquie KE. Oral zinc sulphate in the treatment of recalcitrant viral warts: randomized placebo-controlled clinical trial. Br J Dermatol. 2002;146(3):423–31.
4. Sadighha A. Oral zinc sulphate in recalcitrant multiple viral warts: a pilot study. J Eur Acad Dermatol Venereol. 2009; 23: 715–6.
5. Lopez-Garcia DR, Gomez-Flores M, Arce-Mendoza AY,de la Fuente-Garcia A, Ocampo-Candiani J. Oral zinc sulfate for unresponsive cutaneous viral warts: too good to be true? A double-blind, randomized, placebo-controlled trial. Clin Exp Dermatol. 2009;34(8):e984–5.
6. Simonart T, De Maertelaer V. Systemic Treatments for Cutaneous Warts: A Systematic Review. J Dermatolog Treat. 2012;23(1):72-7.
.
The role of oral zinc sulfate in the treatment of viral warts can be summarized as unknown. Natural Standard database concluded that there is unclear scientific evidence for use of oral zinc sulfate in treatment of viral warts. 1 As if often the case with natural health products there are no clear definitive guidelines for when oral zinc sulfate therapy would be most effective or appropriate. There is clearly not enough evidence to recommend oral zinc sulfate therapy as a first line treatment option and probably even as a second or third line treatment option.
The most promising evidence regarding oral zinc sulfate use in viral wart treatment has been in patients suffering from multiple warts, for lengthy periods of time, and who have previously failed other treatment options. 2-4 There is one well designed study that failed to find any difference between treatment with placebo and treatment with oral zinc sulfate, however the primary endpoint failed to reach statistical significance.5 At the point in time where a patient is still suffering from multiple wart lesions and is running out of treatment options, oral zinc sulfate may present a reasonable option. The studied dose of oral zinc sulfate is most commonly 10mg/kg/day to a maximum of 600mg/day for 2 months. 2-4 There is also a potential that patients with low serum zinc levels may be more likely to respond to treatment however this has yet to be clearly demonstrated.3 It is also important to note that highly varying populations have studied the effect of oral zinc sulfate on the treatment of viral warts and found different results; this suggests that a population-specific demographic, such as diet, may play a role in response to oral zinc sulfate therapy. 2-5 A systematic review evaluating the efficacy of oral zinc sulfate in the treatment of viral warts found a favourable cure rate of 64% that reached statistical significance and had an odds ratio of 17; however the review noted the poor quality of data may affect these overall results. 6
Adverse events reported are consistently of gastrointestinal nature and usually include nausea, vomiting, and epigastric pain. 2-5 Adverse events were lower in one study that gave the total dose of zinc in three divided dose with the express purpose of decreasing gastrointestinal side effects and reported subsequent lower rates of gastrointestinal upset. 3
References
1. Natural Standard. [Internet]. Professional Monograph. [Updated June 2012; cited on June 26, 2012. Zinc. Available at http://www.naturalstandard.com/databases/herbssupplements/all/zinc.asp.
2. Mun S, Kim S, Jung D, et al. Oral zinc sulfate treatment for viral warts: An open-label study. J Dermatolog. 2011;38(6):541–5.
3. Al-Gurairi FT, Al-Waiz M, Sharquie KE. Oral zinc sulphate in the treatment of recalcitrant viral warts: randomized placebo-controlled clinical trial. Br J Dermatol. 2002;146(3):423–31.
4. Sadighha A. Oral zinc sulphate in recalcitrant multiple viral warts: a pilot study. J Eur Acad Dermatol Venereol. 2009; 23: 715–6.
5. Lopez-Garcia DR, Gomez-Flores M, Arce-Mendoza AY,de la Fuente-Garcia A, Ocampo-Candiani J. Oral zinc sulfate for unresponsive cutaneous viral warts: too good to be true? A double-blind, randomized, placebo-controlled trial. Clin Exp Dermatol. 2009;34(8):e984–5.
6. Simonart T, De Maertelaer V. Systemic Treatments for Cutaneous Warts: A Systematic Review. J Dermatolog Treat. 2012;23(1):72-7.
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