112 ANTIPERSPIRANTS
Tannins
Witch Hazel
Botox (onabotulinum toxin A)
Milkvetch Figure 3: Examples of antiperspirant ingredients from nature.
Bioactivities Before discussing active phytochemicals in detail for application as antiperspirants, let us briefly review the other categories of ingredients that are used in underarm products, antiperspirants or deodorants, to better understand what they actually do.
Aluminium and aluminium-zirconium - based salts
These drug actives function by superficial plugging of the eccrine sweat gland ducts (Fig 1) in the stratum corneum layer of the skin by an aluminum hydroxide gel. Due to their acidic nature, the aluminum salts diffuse into the sweat ducts and then proteins in the duct are aggregated by the hydrolyzed aluminium polycations. Per the FDA, these actives must reduce perspiration output by a minimum of 20% to be labelled as antiperspirants, and they can be promoted as “extra effective” if they reduce perspiration by a minimum of 30%. This is demonstrated in hot room clinical testing. Clinical Strength products are an industry developed category, and these products, due to the active type and concentrations used, have been demonstrated to achieve higher sweat reductions, sometimes up to about 60%.
Astringents
These materials are used in cosmetics to cause contraction/shrinkage/tightening of the skin and skin pores, and some also
PERSONAL CARE EUROPE
provide antibacterial benefits. It is believed that certain types of these agents, such as tannic acid, formaldehyde, and glutaraldehyde, can denature proteins in the stratum corneum lining the sweat glands which results in a partial closure of the sweat duct. Some sweat testing was done in the past on palm and plantar surfaces, but positive clinical benefits for axillary sweating were never demonstrated. Today, these kinds of agents are considered obsolete. More acceptable cosmetic grade astringents, such as witch hazel, calendula, specific essential oils, sage, and black tea, can currently be found in underarm deodorants, but no therapeutic benefits have been established.
Absorbents
In general, these are substances used to absorb hydrosoluble, dissolved liposoluble, or finely dispersed substances. They are used in a wide variety of cosmetic products to reportedly absorb moisture, sebum, skin oils, etc., and some powders due to their porous nature reportedly can adsorb odour molecules. Common cosmetic grade absorbents found in underarm deodorants include activated charcoal, arrowroot powder, corn starch, kaolin clay, bentonite, talc, magnesium oxide (MgO), and ZnO. In the last few years, at least a dozen stick deodorants have been introduced in the market that contain one or more of these absorbents. Published, scientifically
supported evidence that these deodorants absorb sweat or odour molecules is generally lacking. In the early 1990s, Elida Gibbs (Unilever) test marketed Kyomi Deodorant-Antiperspirant that contained a superabsorbent cellulose powder, but the product was not successful in the market for aesthetic and other reasons.
Decreased sweat stimulation One way to decrease sweating is to target the parasympathetic nervous system. This is a useful tactic for people that have excessive sweating (hyperhidrosis) on the face, feet, or hands. Oral anticholinergics are sometimes prescribed for people that suffer from hyperhidrosis who have failed to respond to other antiperspirant treatments. For example, diphemanil methylsulfate is an anticholinergic that has been formulated as both an oral and topical drug for hyperhidrosis. Topical anticholinergics generally have less undesirable side effects than oral and they can be used to treat sweating only in the problem areas. In 2004, the US FDA approved Botox® (onabotulinum toxin A) injections for the treatment of severe primary axillary hyperhidrosis. The toxin binds to receptors located on the presynaptic membrane of axons, temporarily blocking the release of acetylcholine.1
This prevents the
hyperstimulation of eccrine sweat glands (Fig 1). In 2018, the FDA approved Qbrexza (glycopyrronium cloth, 2.4%, for topical use)
April 2020
Arrowroot starch
Halloysite
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180 |
Page 181 |
Page 182 |
Page 183 |
Page 184 |
Page 185 |
Page 186 |
Page 187 |
Page 188 |
Page 189 |
Page 190 |
Page 191 |
Page 192 |
Page 193 |
Page 194 |
Page 195 |
Page 196
