Skin care product packaging is supposed to provide consumers with important user information, protect the ingredients, and be easy to use. This is really important for all skin care product users....BUT ESPECIALLY IMPORTANT FOR PEOPLE WITH SENSITIVE SKIN.
The short answer:
1. use products that are in opaque airless pumps
2. use up all the product within 1 year after first application
3. if the product changes colour or smells differently from when you first got it, throw it out!
The long answer:
Protecting the ingredients is critical. All natural/organic (aka plant-based) ingredients will oxidize when exposed to air, bacteria can be introduced to the product by human contact, heat and sunlight will help break down any natural or organic ingredient. If you are leaving the product on your skin, you want to be sure they are as 'fresh' as possible, the action ingredients are not diminished, and there is little chance for irritation (bad product ingredients are definitely going to irritate the skin). The best ways to protect product ingredients is by way of an opaque container with an airless pump. That means that light won't affect the ingredients, and no air gets into the container after you have taken some product out. This is critical for products that you leave on the skin (like moisturizers and serums). Although ideal for all products, it is not as critical for wash-off products like cleansers and exfoliators.
Airless pump containers are more expensive for manufacturers to use - so are less likely to be available for the cheaper drug store products....but for sensitive skin people, these airless pump containers are essential.
The worst type of containers are wide-mouthed jars and see-through glass or plastic containers. The ingredients in such containers will be affected by light and air. Sure the company can counter these impacts by adding more 'preservative' ingredients to protect the others from the light and air...but do you really want more ingredients in your product? Especially when such preservatives generally have a greater potential to be irritants on the skin....maybe that's why you find your skin 'reacts' to so many different products?
The crazy thing is that so many natural/organic products are packaged in open mouthed jars! Why? It seems absolutely insane as far as I'm concerned...
Would you not be prepared to put up with a little inconvenience of not 'seeing' how much product is left, in order to have safer products to apply to your skin? You can always get a 'sense' of how much is left because the container will feel quite 'light-weight'.
Bad product smells differently from when you first got it, and may also have changed colour. Vitamin C and Vitamin A will definitely change colour when they oxidize... DO NOT USE PRODUCT THAT HAS CHANGED COLOUR OR SMELL!
The user information provides the directions for using the product, any warnings, company contact information, and list of ingredients. Ideally all this information should be on the container, because most people throw out the cardboard box. Many companies don't provide a full ingredient list on their website so when you dispose of the box and information sheet you have no source of reference should something go wrong. How do you know if you are using it correctly? It's better to buy products that have all ingredients and directions printed directly on the product container.
The packaging may also provide information on expiration date - though this is not a requirement by the FDA. The general rule of thumb is that the product is good for 1 year after YOU open the container and start using it. This is the European standard for presenting expiration information and is usually a small graphic of a jar with the lid half off and the number 12 to denote 12 months. This is a critical element for you to remember when using products in wide-mouthed jars and regular tubes and bottles. For airless pumps, this 'use-by-date' is longer than a year, but no organization has tested it and is prepared to commit to a definite period of time. Some manufacturers will provide an expiration date that is usually 2 years from the date of manufacture.
Because there is no regulatory standard, and manufacturers may apply different standards to different products, it is easier for you to just buy as many of your products in airless pumps as possible, and to use them up within a year of first using it.
In an article by Michelle Calvarese (Phd) in the January 2014 edition of Skin Inc magazine P 48 - 52, the main criteria manufacturers use for product packaging are:
1. Functionality (does the container dispense the product adequately - thick creams will clog in a pump container/ can the ingredients 'leach' dangerous or irritating chemicals from the plastic container into the product itself - this is essential for acidic and essential oil type ingredients)
2. Ingredient protection (will light or air degrade the ingredients and make them ineffective or potential skin irritants)
3. Client experience (easy to use, non breakable container, easy to dispense the correct amount to be used per application).
For sensitive skin, the main criteria is #2 - Ingredient protection. Functionality will be critical based on the viscosity of the product (very fluid product may leak, thick product may clog and be hard to get all the product out....so you may waste a fair amount because you cannot get it out of the container). The Sensitive Skin Clinic products are based on the smart packaging decisions.