The Ordinary Conflicts – So apart from all the confusing names and layering, you also need to understand about The Ordinary products that conflict. I highly recommend you read through this page and the official Deciem Regimen Page so you understand which products can and can´t be used together.

*The Ordinary Niacinamide Powder – this hasn’t been added to the chart yet. Please check the page direct for products you can and cannot mix it with.

Conflicting & Non-Conflicting Products

Below is a chart using the information given by Deciem on their regimen page. Only the products that have conflicts are mentioned in the first chart. If you use other brands, then you need to check their ingredients too.

On the official regimen page there are some conflicts that are missing, but I think I have covered most of these in the chart below. If you spot any mistakes please let me know. There is now an easier page The Ordinary products you can and cannot mix.

This chart is regularly updated and is a guide only so please link to it rather than a screenshot. Always check the official website Deciem.

Please note the Vitamin C Derivatives should not be used with The Ordinary Niacinamide Powder

• Always read the instructions before using a product. You can find all details on the individual product pages on the Deciem website or on the regimen page.
• Patch testing is highly recommended.
• Whilst they are not mentioned as conflicts, Deciem often says to avoid using Retinols/Retinoids, Pure Vitamin C, and Direct Acids in the same routine to avoid irritation, especially if you´re new to skincare or have sensitive skin.
• Deciem has now mentioned that it´s best to avoid Buffet + Copper with Retinols & Retinoids.
• Whilst I love you sharing this chart, please link to the page directly rather than screenshot as this page /chart is regularly updated.
• This is just a guide and this page takes no responsibility for any problems caused by not reading the instructions first or doing a patch test.

The Ordinary Conflicts Chart with all products with and without conflicts

The Ordinary Products With No Conflicts

Vitamin C Products – Derivatives

Please note that these derivatives should not be used with The Ordinary Niacinamide Powder

• Magnesium Ascorbyl Phosphate
• Ascorbyl Tetraisolpalmitate
• Ascorbyl Glucoside

More Molecules

• Alpha Arbutin
• Caffeine Solution

Oils & Hydration

• B Oil
• Marula Oil
• Moroccan Argan Oil
• Rose Hip Seed Oil
• Chia Seed Oil
• Sea-Buckthorn Fruit Oil
• Hemi-Squalane
• Amino Acids
• Hyaluronic Acid
• Marine Hyaluronics
• Natural Moisturising Factors

What Deciem say about using Peptides & Acids in the same routine

Our rule against combining strong antioxidants only applies to our products containing copper peptides. We would not recommend combining direct acids with peptides due to the susceptibility of peptides to hydrolysis (which breaks the bonds between peptides, reducing their efficacy and making them into individual amino acids). At low pH, the peptides undergo processes such as deamidation (the removal of an amide group) and oxidation, which compromise the activity of the peptides.

Having said that, if you have previously combined peptides with acids and have not experienced any negative side effects or discoloration, you may continue to combine the two products as so as the combination does not pose any potential harm. Our recommendations are meant to serve as a preventative measure to avoid any incompatibility between those combinations and also because skin tolerance in subjective. 

The Ordinary Peptides

Peptides are Buffet, Buffet + Copper, Matrixyl and Argireline. Buffet + Copper Peptides has a few more conflicts than the others. Always read the instructions and double–check with Deciem if you’re unsure.

The Ordinary Vitamin C Products

Why can’t I mix Niacinamide with Vitamin C? This is one of the most common questions in the Facebook Group as Deciem says to avoid using in the same routine, whilst many other companies use them together. Here´s their response.

Deciem say: Our contraindication is specific to our products and their concentrations. If you’ve used them together in the past and the combination has worked for you without any issues, you may continue to do so.

These are the pure vitamin C products

• Vitamin C 23%
• Vitamin C 30%
• Ascorbic Acid 8% + Alpha Arbutin 2%
• Ethylated Ascorbic Acid 15% Solution
• 100% L-Ascorbic Acid Powder

Other The Ordinary Conflicts & Conflicting Information

If you follow Deciem on Instagram, they suggest using Retinoids / Retinols, Acids, and Vitamin Cs in different routines due to irritation. There’s also conflicting information about Niacinamide and Vitamin C. The more you read on the internet the more confusing it will be with conflicting advice, but it´s important to read and learn.

If you are an experienced skincare user then I’m sure you have done your homework and know what’s best for your skin. For those of you who are new to skincare, it´s really down to you to decide whose advice to take. Personally, if I’m using Deciem products then I will take their advice. Remember, they do recommend patch testing and it´s good practice to patch test when you introduce 2 products in case of irritation.

The Ordinary Skincare Routines

• General Signs of Ageing Regimen
• Pigmentation Regimen
• Dehydration Regimen
• Look of Blemishes & Congestion
• Textural Irregularities Regimen
• Rosacea Regimen
• Oily Skin Regimen
• Sensitive Skin Routine
• Personalised routines in the Facebook Group, NIOD & Hylamide routines