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Bayer’s ‘Shamrock’ Package Cures Design Headaches

Cloverleaf-shaped strip-pack, customized machinery provide peel-open consumer convenience and market differentiation for fast-acting Bayer aspirin.

Shown here is Bayer’s Shamrock aspirin pack next to its outer folding carton.
Shown here is Bayer’s Shamrock aspirin pack next to its outer folding carton.

Known as a young sprig of clover, the shamrock is a symbol of Ireland typically associated with Saint Patrick’s Day that was traditionally used for medicinal purposes. Today, it’s a cloverleaf-shaped “Shamrock” blister package for a fast-acting aspirin that’s bringing good luck for Bayer AG, the Leverkusen, Germany-based lifescience company.

Packaging of Bayer ASPIRIN® 500 MG aspirin is done at the company’s manufacturing plant in Bitterfeld, Germany. That’s where Bayer produces over-the-counter solid-dose pharmaceutical powders, granules and tablets, including this aspirin. The cloverleaf-shaped shamrock package contains four aspirin, one tablet within each of the four cavities within this unique four-pack. Different multiples of these shamrock packs are subsequently placed within an outer folding carton for over-the-counter sales. The package is sold in some European countries, Latin-America, Mexico, and Brazil.

Dr. Wolfgang Fischer, Head of Process Technology, Consumer Health Division, Bayer Bitterfeld GMbH, says the aspirin is a chemical form of acetylsalicylic acid. “It provides pain relief in 15 minutes, about half the time as competitive products. I don’t think our competitors offer anything like it,” he says.

At his Feb. 28 keynote presentation at the Healthcare Packaging & Processing Conference held in conjunction with PACK EXPO East in Philadelphia, Guido Schmitz, Head of Packaging and Technology Innovation at Bayer Healthcare, described the product as a new kind of aspirin, one whose key differentiation from the aspirin products sold by Bayer for the last 120 years is that it dissolves far more rapidly upon ingestion.

To complement this new aspirin, Schmitz says Bayer sought a very different packaging format, which would require a significant capital investment. If that wasn’t enough of a challenge, the packaging had to address the product’s susceptibility to humidity damage.

Fischer says the Bitterfeld facility uses two packaging lines for the Shamrock packages. “Some of the packaging machinery is identical on the two lines, some not,” he explains. “It depends on the market where we are selling the product. In Latin-American countries, for example, they use large 80- and 100-count packs.” One of the reasons for the larger packs used in this market is that pharmacists can remove a single four-pack from the carton and sell it along with a product leaflet.

Overcoming a tough U.S. start

Initially, the Bayer U.S. team worked with packaging partner Romaco to brainstorm packaging ideas, which led to the use of a strip pack with a design that ultimately resulted in the Shamrock blister.

In the U.S., however, consumers are more familiar with taking smaller-sized aspirin from a bottle. So, despite Bayer’s affection for the strip pack design, Fischer explains, “This formulation was launched in the U.S. in 2013 in a high-density polyethylene bottle, which included a desiccant, but it wasn't successful.”

Why not? Fischer says, “I think product degradation was a key reason why. Each time you take a tablet out of the bottle you introduce more humidity. So when you pour out tablets and they touch your humid palm and you put the rest of the tablets back into the bottle, that’s enough humidity to start the degradation of the product. When you open the bottle the next time it might smell of acetic acid from this product degradation, which we believe is a reason why people didn't like this product.” Within months, he says, Bayer stopped production of the product and package in the U.S.

After making an economic investment in both the new aspirin product and packaging research, it’s understandable that Bayer wanted to sell the product in other geographic markets.

“We were looking to avoid the human contact and the challenges of humidity,” Fischer recalls. “In Europe, blisters and pouches are common. Even though aluminum packs were expensive compared to blisters, we felt we had a good product and the foil could maintain product stability much better [than a plastic bottle].”

Peel open, not push-through

In moving forward with the Shamrock package, Bayer found a materials supplier in LEIPA in Germany. Fischer describes the structure as a top-and-bottom foil construction with a polyethylene-based adhesive layer. The aluminum provides humidity barrier and child-resistance.

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INTRODUCING! The Latest Trends for Life Sciences at PACK EXPO Southeast