With the increasing number of insect repellent patches on the market people frequently ask the question, “do they work”? My short retort is a resounding, NO!” Here you will get the facts as to why not.
These thiamine patches must be applied 2 hours before exposure –this is not always practical when you don’t know mosquitoes are going to be at large. They also have to be ripped off the skin like a band aid.
Some people swear by Patches usually containing Vitamin B1 (Thiamine) sometimes with other B vitamins along with other ingredients such as aloe vera in the case of Don’t Bug Me – you do get a hint of these products effectiveness by what is written on their label:
“The other ingredient, Aloe, serves as an anti-inflammatory agent, minimizing the reaction in the event you do experience a bite.”
These people who swear by Thiamine either in patch or tablet form are certainly not getting bitten, but this is because of other factors; one of these could be that they are so certain that they will not get a bite, they do not -the placebo effect. Some scientists believe that most of the people not getting bitten when they apply B1 patches or eat them, are already naturally repellent.
Another patch manufacturer, DeBug, has the following scientifically accurate information on its web site: “A study suggested that taking thiamine (vitamin B1) 25 mg to 50 mg three times per day is effective in reducing mosquito bites. A large intake of Thiamine produces a skin odor that is not detectable by humans, but is disagreeable to female mosquitoes. (Pediatric Clinics of North America, 16:191, 1969) Thiamine takes more than 2 weeks before the odor fully saturates the skin. With the advances in topical preparations there is an increasing number of Thiamine based repellent products. Whilst there is considerable anecdotal evidence of Thiamine products being effective in the field (Australia, US and Canada), there has yet to be any clinical trials run to demonstrate the efficacy of these products.”
This single test in the 60’s is how we came to believe in the first place that Vit B1 could protect us and now we have all these Vitamin B1 patches. In fact the converse is true, from ALL of the many subsequent tests on mosquito repellent patches or other insect repellent patches, not one study has found them to be effective. The University of Carolina has also stated, “The UNC researchers, however, cited earlier studies that found no ingested compound, such as garlic or vitamin B1, was capable of repelling mosquitoes.”
Pure logic also backs up all this research, a female mosquito is attracted to kairomones, such as carbon dioxide, from up to a kilometer away –according to Dr Hill at the London School of Hygiene & Tropical Medicine. How could relatively small amounts of Vitamin B1 or Garlic possibly mask or shield all that CO2? It just doesn’t make sense, which is why I would never recommend their use.