How to store dog supplements (and keep live cultures live)

What the DIGEST+ label asks

Storage instructions are part of a product’s label for a reason: they are the conditions under which the contents are expected to stay as described until the best-before date. For DIGEST+, the label says:

The best-before date and batch number are printed on the base of the bottle. It is worth glancing at both when a new bottle arrives, and keeping the lid firmly closed between doses. Our guide to reading a dog supplement label explains the other information you’ll find on the pack.

Why storage matters more for live cultures

Most supplement ingredients are fairly stable. Live micro-organisms are different: a product’s stated count — for DIGEST+, 2 billion CFU of its live culture blend per tablet — depends on those bacteria staying viable over the product’s shelf life. (See what CFU means for how that count works.)

A 2019 review of probiotic production in the journal Microorganisms sets out what affects that viability. It identifies water activity — essentially, how much available moisture the product contains — followed closely by storage temperature as the main factors affecting probiotic stability over shelf life. It notes that dry formats such as tablets and capsules are made under strict temperature- and humidity-controlled conditions, that packaging is chosen to limit moisture getting in, and that keeping moisture out helps maintain a viable cell count. It also explains that supplements stored at ambient temperature and humidity may lose some viability compared with refrigerated storage, which is why manufacturers commonly build in an overage so the declared count is still met at the end of shelf life.^[1]

Put simply: dry, cool and closed is what keeps cultures in the condition the label describes. Damp, warm and open is what works against them.

Where to keep the bottle at home

Should you keep it in the fridge?

You don’t have to, but the DIGEST+ label notes that refrigeration may help extend shelf life, which fits with the research above on temperature and viability. If you do refrigerate it, keep the lid tightly closed, take out what you need and put the bottle straight back. Avoid leaving a cold bottle open in a warm, steamy kitchen, where moisture can condense on cold surfaces — moisture is the factor the review identifies as most important.^[1]

Don’t decant

It is tempting to tip tablets into a pill organiser, a jar or a sandwich bag. The original bottle is better for several reasons: the review notes that supplement packaging is chosen for how well it keeps moisture out, so an everyday container may not offer the same protection; every opening of a loosely sealed container lets in air and humidity; and decanting separates the tablets from the batch number and best-before date on the bottle base. If you need a day’s tablets on the go, take out only what you need for that day.^[1]

Travelling, and why the car is the worst cupboard

A parked car heats up fast. The PDSA notes that on a 22°C day the inside of a car can reach 47°C within an hour, and that parking in the shade or leaving a window open a crack won’t stop it. That is a serious danger to your dog first and foremost — never leave a dog in a parked car on a warm day — and it is also far outside ‘cool, dry place’ for anything you are carrying.^[4]

Our guide to travelling with your dog covers the wider routine — food, water and breaks — for trips away.

Best-before dates and out-of-date product

On UK food labelling, best-before dates relate to quality, whereas use-by dates relate to safety. GOV.UK’s guidance also points out that food not stored as the label instructs can reduce in quality before the best-before date — a useful principle for any product with storage instructions.^[2]

The probiotic review notes that supplements should deliver the count declared on the label throughout the product’s shelf life — which assumes the product has been stored as directed. After the best-before date, or if a bottle has been left somewhere hot or damp, you can no longer rely on the product being as described. Rather than finishing an old bottle, start a fresh one and dispose of the old tablets as the packaging advises, keeping them out of reach of pets in the meantime. If tablets look or smell unusual, have become soft or crumbly, or the bottle got wet, don’t use them.^[1]

If you have several dogs, a bottle goes faster — see dosing in a multi-dog household for how to work out how long one lasts. DIGEST+ is available as single bottles and in 2- and 3-bottle packs, so you can match what you buy to how quickly you use it.

Do and don’t at a glance