Performing Double Duty

Child-resistant (CR) packaging is typically associated with closures that require two simultaneous actions (e.g., squeezing and turning or pressing and turning) or a sequence of actions. In the United States, the Consumer Product Safety Commission requires CR packaging to be senior friendly (SF) as well. Designing a package that is both CR and SF poses significant challenges, but options are increasing.

Hallie Forcinio

For example, pharmaceutical manufacturers that prefer blister packaging traditionally have relied on multilayer lidstock laminations with a peelable paper layer to prevent access by children. However, some new structures are eliminating the paper layer to provide easier access for adults while still protecting children.

One structure incorporates layers of printed foil, adhesive, polyester, and heat-seal coating, and seals at lower temperatures than a conventional paper–polyester laminate does, thus enhancing productivity while reducing the amount of heat exposure that the product experiences. Eliminating the paper layer reduces particulate contamination (easy-PIESY Lidding, Constantia Hueck Foils).

A polyester-based lidstock not only eliminates the paper layer, but is available in three levels of CR protection. The all-film coextrusion or coextruded film–foil structure can be configured for peel, peel–push or tool-aided access to the medication inside and can be designed to meet F = 1 requirements, the highest level of child resistance that the Consumer Product Safety Commission recognizes (Safety-Pak Plus PL, PP, or LT lidstock, Winpak Heat Seal Packaging).

A tiny press-and-turn cap imparts child-resistant and tamper-evident properties to a single-dose tube.

For form–fill–seal packaging such as stick packs, pouches, or barrier overwraps, four standard film constructions provide different degrees of CR protection while maintaining senior friendliness, processability, and performance. The materials can be printed in as many as 10 colors to maximize shelf appeal. Solventless lamination options address sustainability initiatives because they reduce energy consumption by 86% compared with solvent-based laminating processes. Structures compatible with high-speed equipment also are available (Flexi-Free CR barrier overwrap film, Ampac Flexibles, a division of Ampac Packaging).

The F = 1-rated howell
•CR
•III wallet can be made with virgin or recycled-content paperboard.

Another way to impart CR protection is to put a non-CR blister into a CR wallet. Many wallet designs also serve as compliance packages, starter kits, or titration regimens.

One patented wallet pack seals a non-CR blister into a paperboard sleeve to create a CR package (howell•CR•III package, Howell Packaging). A configuration using paperboard with recycled content also has earned an F = 1 rating. At least two machines can join the blister card and paperboard. One is capable of running 50–75 packs/min (wallet pack machine, Howell Packaging), and another produces more than 200/min (Blister Card/Wallet Machine, MGS Machine).

Intini’s Bend and Peel Easy Tab wallet with a folded double card provides child resistance protection for high pill counts.

Another wallet concept relies on an open-ended, flat paperboard carton with matching oval windows in the top and bottom panels. It also incorporates a die-cut tab in the blister to lock the card in place. Pushing the die-cut tab up unlocks the blister and allows the card to slide out. An interior stop prevents the card from being completely removed from the seal- or tuck-end carton. After the user removes the dose by pushing it through the lidstock, he or she slides the card back into the carton and presses the tab down to lock it in place. Poly-coated paperboard protects the carton from tearing, and the configuration is often compatible with existing blister tooling. Adult testers rated the design as easy to manipulate. Toddler testers had such difficulty with access that the package earned an F = 1 rating (F1 Easy Lock wallet, Intini Marketing).

Intini’s F = 1 Easy Lock wallet unlocks the blister card by pushing up a die-cut tab. An interior stop prevents removal of the card from the sleeve.

A similar pull-out–push-in design with an F = 1 rating earned praise from the Arthritis Foundation for its ease of use. The integrated carton, blister card, and leaflet or insert features an easy push-through lidstock plus a calendar or set of dosing instructions to help the patient remember when to take a pill. To earn the commendation, the package underwent a series of rigorous tests at the Georgia Institute of Technology's Research Institute, an independent laboratory that analyzes products for people with functional limitations resulting from arthritis. The study participants, who have moderate to severe arthritis, found the design easy to use, and six out of eight participants would recommend the design to friends with arthritis (Dosepak Express, MeadWestvaco).

Most child-resistant wallet designs from Intini accept cold-formed foil blisters as well as standard blisters.

If a capsule or tablet is too fragile to be pushed through lidding material, CR protection is still possible through a folded, heat-sealable paperboard card with a perforated tab and a dual-chamber blister (i.e., one empty and one full chamber). To access the dose, the user tears away the paperboard tab, presses down on the empty blister chamber to break the lidstock, and tears the lidstock to free the dose in the second chamber. Suitable for clinical trials, the design also is licensed for use by the Veterans Administration (Peel Peel wallet, Intini).

A child-resistant wallet design from Intini holds a blister card with a dual-chamber configuration to provide access to doses that are too fragile to be pushed through lidding material.

For sturdier doses, a similar concept starts with pressing out a perforated tab with a key, tearing the tab away to expose the foil lidstock, and pushing the pill through (3CPak, Colonial Carton) A low-volume version for clinical trials also is available (Key-Pak, Keystone Folding Box).

A similar paperboard wallet design with perforated tabs calls for bending the edge of the wallet to gain access to the tab. When the tab is removed, a layer of paperboard with an I-shaped die cut remains. The die cut reduces the force needed to push the pill through the lidstock and paperboard layer. The intuitive design eliminates the need for printed instructions, thus leaving more space for product information and graphics.

For regimens with high pill counts, a folded double card can be housed in an open-ended, tuck-style carton. Blisters can be traditional film–foil or cold-formed foil. Ranking as the first CR and SF blister pack approved by the Canadian Standards Association, the design also meets US and European requirements for CR packaging (Bend and Peel Easy Tab wallet, Intini).

Another folded-wallet design can be assembled semiautomatically or automatically. The booklike configuration provides ample space for product information and vivid graphics (CRx Pack, Pharma Packaging Solutions, a division of Carton Service).

Other designs bring CR protection to injection-molded containers. Designed to be reusable, a recyclable hinged container can be sized and shaped to hold vials, blisters, aerosols, autoinjectors, patches, mists, pumps, and syringes. Releasing the lid requires two hands, one putting pressure in one area on the base of the container, and the other pressing down on latches on opposite ends of the integral lid. A version of the F = 1-rated container that holds multiple blisters could be used by pharmacies for prescriptions (Medi-Lock CR Container, Intini).

A related two-piece container dispenses doses singly while providing F = 1 protection. It can be sized to handle virtually any tablet and is compatible with high-speed, automated filling lines (Medi-Lock Top Lock Slider Pack, Intini).

Tube packaging also has CR options. One tiny cap for single-dose tubes also offers tamper-evident protection. Like many CR concepts, the closure requires a dual movement. The outer cap rotates freely unless it is pushed in to interlock with the inner cap. Pressing and turning releases an inner pin and opens the tube at a defined breaking point, while the cap remains on the tube body during dispensing. An ergonomic nozzle enables precise application of the liquid or cream without allowing the contents to be contaminated. The design is certified as CR and suitable for adults according to testing carried out in accordance with 16 CFR 1700.20 and EN 14375. Applications include topical treatments, dietary supplements, concentrates or laboratory substances, product samples, and travel-size products (Twist'n'Use CR Polyfoil tube, Neopac).

For larger tubes, CR closures are available in a diameter of 18 mm (CR Tube-Lok closure, Berry Plastics). For on-the-go applications, a small integrated push-and-turn closure–vial combination holds a short stack of pills. It's offered in 16-mm or 20-mm diameters (Pursepak package, Berry Plastics).

Hallie Forcinio is Pharmaceutical Technology's Packaging Forum editor, 4708 Morningside Drive, Cleveland, OH 44109, tel. 216.351.5824, fax 216.351.5684, editorhal@cs.com.