According to media reports, 100,000 people are on the waiting list for No7 Advanced Retinol 1.5% Complex Night Concentrate, priced at £34.
It is the longest ever waiting list for a new product.
Around 48,000 people registered for early access before the launch last Thursday, while now the list has over 99,000 names on it.
Boots says the new formula delivers retinol, an ingredient derived from vitamin A, in a more effective form with a lower dosage – 0.3% instead of 1%, which can cause redness, peeling and discomfort.
Retinoic acid has been used to treat acne for 50 years but it has become popular as an anti-ageing ingredient that claims to increase epidermal thickness and skin cell renewal.
“The news is significant beyond being a growth driver for Croda's personal care business because it shows the enduring consumer interest in anti-ageing, anti-wrinkle skincare, the scope for these products to sell online and Croda's position as a leader in the skincare actives business,” analysts at Liberum said.
Shares dipped 1% to 5,050p on Tuesday before close.