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Dr. Barbara Stürm Sun Drops SPF 50 Us Formula

Sun Drops SPF 50 Us Formula

Sunscreen drops that can be added to your moisturizer
Uploaded by: 4narow on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Homosalate (10.0%) sunscreen
Octinoxate (7.5%) sunscreen 0, 0
Octisalate (5.0%) sunscreen 0, 0
Avobenzone (3.0%) sunscreen goodie
Aqua/Water/Eau solvent
Butyloctyl Salicylate solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Styrene/Acrylates Copolymer
Potassium Cetyl Phosphate emulsifying, surfactant/​cleansing
Cyclopentasiloxane emollient, solvent
Glyceryl Stearate emollient, emulsifying 0, 1-2
PEG-100 Stearate surfactant/​cleansing, emulsifying 0, 0
Aluminum Starch Octenylsuccinate viscosity controlling
Portulaca Oleracea (Purslane) Extract soothing, antioxidant goodie
Phenoxyethanol preservative
Tocopherol Acetate antioxidant 0, 0
Polyacrylate-13
Xanthan Gum viscosity controlling
Pentylene Glycol solvent, moisturizer/​humectant
Benzoic Acid preservative
Ethylhexylglycerin preservative
Glycereth-2 Cocoate emulsifying, surfactant/​cleansing
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Polyisobutene viscosity controlling
Polysorbate 20 emulsifying, surfactant/​cleansing 0, 0
Panthenol soothing, moisturizer/​humectant 0, 0 goodie
Arginine skin-identical ingredient goodie
Sodium Carboxymethyl Beta-Glucan surfactant/​cleansing, viscosity controlling
Anthemis Nobilis (Chamomile) Flower Extract soothing, perfuming goodie
Camellia Sinensis (Green Tea) Leaf Extract antioxidant, soothing goodie
Cassia Alata (Senna) Leaf Extract soothing, antimicrobial/​antibacterial goodie

Dr. Barbara Stürm Sun Drops SPF 50 Us Formula
Ingredients explained

What-it-does: sunscreen

An oil-soluble chemical sunscreen agent that protects the skin from UVB (295-315 nm) with a peak protection at 306 nm. Homosalate is not a strong UV filter in and of itself (gives only SPF 4.3 protection at max. allowed 10% concentration) and it is not photostable (looses 10% of its SPF protection in 45 mins) so it always has to be combined with other sunscreens for proper protection. Its big advantage, though, is that it is a liquid and is excellent for dissolving other hard to solubilize powder sunscreen agents, like the famous Avobenzone.

Regarding Homosalate's safety profile, we do not have the best news. In-vitro (made in the labs) studies have shown that it might have some estrogenic activity. Do not panic, these studies were not conducted on real humans under real world conditions. Still, if you are a 'better safe than sorry' type, be careful when using Homosalate containing sunscreens long-term and full-body.

Also-called: Octinoxate, Octyl Methoxycinnamate;Ethylhexyl Methoxycinnamate | What-it-does: sunscreen | Irritancy: 0 | Comedogenicity: 0

A clear, oil-soluble, "cosmetically-elegant" liquid that is the most commonly used chemical sunscreen. It absorbs UVB radiation (at wavelengths: 280-320 nm) with a peak protection at 310nm. 

It only protects against UVB and not UVA rays (the 320-400 nm range) – so always choose products that contain other sunscreens too. It is not very stable either, when exposed to sunlight, it kind of breaks down and loses its effectiveness (not instantly, but over time - it loses 10% of its SPF protection ability within 35 mins). To make it more stable it can be - and should be - combined with other sunscreen agents to give stable and broad-spectrum protection (the new generation sunscreen agent, Tinosorb S is a particularly good one for that).

Also-called: Octyl Salicylate, Octisalate;Ethylhexyl Salicylate | What-it-does: sunscreen | Irritancy: 0 | Comedogenicity: 0

A colorless to light yellowish oily liquid that works as a UVB (280-320nm) sunscreen filter with a peak absorbance at 306 nm. It's not a strong filter in itself, it's always used in combination with other sunscreen agents to further enhance the SPF and to solubilize other solid UV filters.

It has a good safety profile and is allowed to be used at a max concentration of 5% both in the US and in Europe (10% is allowed in Japan).

Also-called: Butyl Methoxydibenzoylmethane | What-it-does: sunscreen

The famous Avobenzone. It is a special snowflake as it is the only globally available chemical sunscreen agent that provides proper UVA protection (in the US, new generation sunscreen agents are not approved because of impossible FDA regulations). It is the global gold standard of UVA protection and is the most used UVA sunscreen in the world. 

It gives very good protection across the whole UVA range (310-400 nm that is both UVA1 and UVA2) with a peak protection at 360 nm. The problem with it, though, is that it is not photostable and degrades in the sunlight. Wikipedia says that avobenzone loses 36% of its UV-absorption capacity after just one hour of sunlight (yep, this is one of the reasons why sunscreens have to be reapplied after a few hours).

Also-called: Aqua;Water | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

What-it-does: solvent

A nice, multi-functional helper ingredient that's especially useful in sunscreens. It can solubilize some commonly used UV-filters like Oxybenzone or Avobenzone and it can also help to increase the SPF rating of sunscreens. It's also cosmetically elegant, has excellent spreadability and a pleasant, moisturizing skin feel. Oh, and according to Wikipedia, it even helps to stabilize famously unstable UVA-filter, Avobenzone.

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

A film-forming polymer (big molecule from repeated subunits) to create water-resistant sunscreen formulas. It also improves the SPF value of sunscreen formulas (approx. 11-18% boost in SPF per 1% Styrene/Acrylates Copolymer). 

A white to beige powder that is described as the golden standard emulsifier for emulsions (oil+water mixtures) that are difficult to stabilize. It is especially popular in sunscreens as it can boost SPF protection and increase the water-resistance of the formula. 

What-it-does: emollient, solvent

A super commonly used 5 unit long, cyclic structured silicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel

It's often combined with the non-volatile (i.e. stays on the skin) dimethicone as the two together form a water-resistant, breathable protective barrier on the skin without a negative tacky feel.

What-it-does: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

What-it-does: surfactant/cleansing, emulsifying | Irritancy: 0 | Comedogenicity: 0

A very common water-loving surfactant and emulsifier that helps to keep water and oil mixed nicely together. 

It's often paired with glyceryl stearate - the two together form a super effective emulsifier duo that's salt and acid tolerant and works over a wide pH range. It also gives a "pleasing product aesthetics", so no wonder it's popular.

A handy helper ingredient that comes in a white powder form and works as an anti-caking and oil-absorbing agent. It also gives products good spreadability, long lasting and velvet touch characteristics. It is popular both in skincare and makeup products.

Also-called: Purslane Extract | What-it-does: soothing, antioxidant

Portulaca Oleracea is a nice succulent with bright yellow flowers and edible nutritious vegetables. It's a famous plant in Korean traditional medicine to treat infection and irritated skin.

Modern research confirms that it's loaded with skin-goodies: it's the richest green plant source of omega-3 fatty acids (α-linolenic acid), contains NMFs (polysaccharides and amino acids),  vitamins (β-carotene), minerals, and antioxidants (yellow betaxanthins and reddish betacyanins). Thanks to all its beneficial components, Purslane Extract has several magic properties: it's a great anti-inflammatory and antioxidant agent and also has wound healing abilities

What-it-does: preservative

It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.

It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic. 

Also-called: Vitamin E Acetate;Tocopheryl Acetate | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 0

It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version. 

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E. 

A helper ingredient that functions as a film-forming polymer (big molecule from repeated subunits).

It usually comes to the formula as part of a thickener-emulsifier trio paired with Polyisobutene and Polysorbate 20. The three togeather have excellent thickening properties with remarkable emulsifying-stabilising abilities. They also have a nice silicone feel with glide-on spreading. 

It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range. 

Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415). 

A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also a moisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improve water-resistance of sunscreens. 

What-it-does: preservative

An Ecocert-approved, natural preservative that counts as gentle and non-irritating to the skin. Usually, it comes to the formula as part of a preservative blend as it's not enough on its own.

What-it-does: preservative, deodorant

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.

Also, it's an effective deodorant and a medium spreading emollient

We don't have description for this ingredient yet.

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

What-it-does: viscosity controlling

A polymer (big molecule from repeated subunits) that's used as a gloss improver for lipsticks and lipglosses. Its stickiness also helps lip products to stay on longer. 

Combined with polyacrylate-13 and polysorbate 20, it forms a very effective tickener-emulsifier trio.

What-it-does: emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0

It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 

Panthenol - goodie
Also-called: Pro-Vitamin B5 | What-it-does: soothing, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

An easy-to-formulate, commonly used, nice to have ingredient that’s also called pro-vitamin B5. As you might guess from the “pro” part, it’s a precursor to vitamin B5 (whose fancy name is pantothenic acid). 

Its main job in skincare products is to moisturise the skin. It’s a humectant meaning that it can help the skin to attract water and then hold onto it. There is also research showing that panthenol can help our skin to produce more lovely lipids that are important for a strong and healthy skin barrier. 

Arginine - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

We don't have description for this ingredient yet.

Also-called: Roman Chamomile Flower Extract | What-it-does: soothing, perfuming

There are two primary types of Chamomile, the German and the Roman. Both has soothing properties, but the German one contains more anti-inflammatory actives (like chamazulene). The anti-inflammatory action of the Roman Chamomile is due to phenolic compounds and -  according to manufacturer info- it also has some nice skin toning properties.

Also-called: Green Tea | What-it-does: antioxidant, soothing
  • Green tea is one of the most researched natural ingredients
  • The active parts are called polyphenols, or more precisely catechins (EGCG being the most abundant and most active catechin)
  • There can be huge quality differences between green tea extracts. The good ones contain 50-90% catechins (and often make the product brown and give it a distinctive smell)
  • Green tea is proven to be a great antioxidant, UV protectant, anti-inflammatory, anticarcinogenic and antimicrobial
  • Because of these awesome properties green tea is a great choice for anti-aging and also for skin diseases including rosacea, acne and atopic dermatitis
Read all the geeky details about Camellia Sinensis Leaf Extract here >>

Also-called: Candle Tree Leaf Extract | What-it-does: soothing, antimicrobial/antibacterial, astringent

Candle tree is a nice plant with beautiful yellow flowers that's native to Mexico. It's a medicinal tree that has very effective fungicidal properties and is used traditionally to treat fungal infections of the skin. 

Modern studies confirm antimicrobial as well as anti-inflammatory activity of the tree. According to manufacturer info it's even a great anti-aging plant extract that gives DNA protection from UV rays and supports the natural repairing process of the skin cells. 

You may also want to take a look at...

what‑it‑does sunscreen
An oil-soluble chemical sunscreen agent that protects the skin from UVB (295-315 nm) with a peak protection at 306 nm. Homosalate is not a strong UV filter in and of itself (gives only SPF 4.3 protection at max. [more]
what‑it‑does sunscreen
irritancy, com. 0, 0
Octinoxate - an old-school chemical sunscreen that absorbs UVB radiation (wavelengths: 280-320 nm). Not photostable and does not protect against UVA. [more]
what‑it‑does sunscreen
irritancy, com. 0, 0
A colorless to light yellowish oily liquid that works as a UVB (280-320nm) sunscreen filter with a peak absorbance at 306 nm. It's not a strong filter in itself, it's always used in combination with other sunscreen agents. [more]
what‑it‑does sunscreen
Avobenzone - the only globally available chemical sunscreen that gives proper UVA protection. It is not photostable so has to be combined with ingredients that help to stabilize it. [more]
what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does solvent
Multi-functional helper ingredient in sunscreens. It can solubilize and stabilize commonly used UV-filters and has a cosmetically elegant, emollient skin feel. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
A film-forming polymer (big molecule from repeated subunits) to create water-resistant sunscreen formulas.  [more]
what‑it‑does emulsifying | surfactant/cleansing
A white to beige powder that is the golden standard emulsifier for emulsions (oil+water mixtures) that are difficult to stabilize. [more]
what‑it‑does emollient | solvent
It's a super commonly used water-thin volatile silicone that gives skin and hair a silky, smooth feel.  [more]
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1-2
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
what‑it‑does surfactant/cleansing | emulsifying
irritancy, com. 0, 0
A commonly used water-soluble surfactant and emulsifier. [more]
what‑it‑does viscosity controlling
A handy helper ingredient that comes in a white powder form and works as an anti-caking and oil-absorbing agent. It also gives products good spreadability, long lasting and velvet touch characteristics.
what‑it‑does soothing | antioxidant
Purslane Extract - a traditional Korean medicinal plant with skin-soothing, antioxidant and wound healing abilities. [more]
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [more]
A film forming polymer that usually comes to the formula as part of a thickener-emulsifier trio paired with Polyisobutene and Polysorbate 20. [more]
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does solvent | moisturizer/humectant
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent, and a broad spectrum antimicrobial. [more]
what‑it‑does preservative
An Ecocert-approved, natural preservative that counts as gentle and non-irritating to the skin. Usually, it comes to the formula as part of a preservative blend as it's not enough on its own.
what‑it‑does preservative
It can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too. [more]
what‑it‑does emulsifying | surfactant/cleansing
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does viscosity controlling
A polymer (big molecule from repeated subunits) that's used as a gloss improver for lipsticks and lipglosses. Combined with polyacrylate-13 and polysorbate 20, it forms a very effective tickener-emulsifier trio. [more]
what‑it‑does emulsifying | surfactant/cleansing
irritancy, com. 0, 0
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 
what‑it‑does soothing | moisturizer/humectant
irritancy, com. 0, 0
Pro-Vitamin B5 is a goodie that moisturises the skin, has anti-inflammatory, skin protecting and wound healing properties. [more]
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does surfactant/cleansing | viscosity controlling
what‑it‑does soothing | perfuming
Roman Chamomile - thanks to its phenolic compound had some nice soothing and skin toning properties. It contains less anti-inflammatory actives than the German Chamomile. [more]
what‑it‑does antioxidant | soothing
Green Tea - one of the most researched natural ingredients that contains the superstar actives called catechins. It has proven antioxidant, anti-inflammatory, antimicrobial and anticarcinogenic properties. [more]
what‑it‑does soothing | antimicrobial/antibacterial
Candle Tree - a medicinal tree that has very effective fungicidal properties. Has also anti-inflammatory activity and might give DNA protection from UV rays. [more]