How Lean Can You Safely Run Your Veterinary Inventory?

Every practice manager who has ever stared at a full shelf and a tight month has had the same thought: we are carrying way too much of this. And they're often right. Overstock is real, it's expensive, and most practices have more of it than they think.

The trouble starts with the conclusion people draw next, which is usually some version of "let's run lean, order smaller, keep less on hand." That sounds disciplined. Applied across the board, it's one of the more expensive mistakes a practice can make, because it treats every item on the shelf as the same kind of risk. They are not.

So let's do the actual arithmetic on both sides, and then talk about where leanness should really come from.

Just-in-time is the wrong target for a clinic

Just-in-time is a genuine and successful idea. It comes out of manufacturing, where the goal is to have parts arrive exactly when the line needs them, so nothing sits around absorbing capital.

The reason it works there is that the failure mode is financial. If a part is late, the line stops, you lose a shift, you count the cost and you fix the supply chain.

Your failure mode is not financial. It's a patient in an exam room who needs something today, and a client watching you explain why you don't have it. You can't pause the line. You can't tell a dog with a seizure disorder to come back Thursday. That difference isn't a detail, it's the whole reason manufacturing logic doesn't transfer cleanly to a hospital.

What holding stock actually costs

Carrying inventory isn't free, and the cost is bigger than most people assume because it's spread across categories nobody invoices you for:

• Cost of capital. Money on a shelf is money not in payroll, equipment, or the bank.
• Expiry. The single most visible one in a practice, and the most painful.
• Shrink. Product that walks off, breaks, or gets used without being billed.
• Storage and handling. Space, organization, counting time.

Industry figures for the total run roughly 20% to 30% of inventory value per year. Take the 25% midpoint and the math gets uncomfortably concrete:

$60,000 on your shelves × 25% = $15,000 a year just to hold it

That's the number that makes people want to go lean, and it should. If $18,000 of that $60,000 is genuine overstock, you're spending about $4,500 a year to store product you didn't need to buy yet.

What a stockout actually costs

Now the other side of the ledger, which almost nobody prices out.

When you run out of something, one of a few things happens, and none of them are free:

• The emergency fill. You source it from a secondary supplier at a worse price, often with expedited shipping. Call it a 20% premium plus a rush freight charge.
• Staff time. Twenty minutes of a licensed person calling around is twenty minutes not spent on a patient or a client.
• The lost sale. The client fills it at an online pharmacy instead. This is the expensive one, because you frequently don't lose one fill, you lose the refill stream behind it.
• The clinical cost. Hardest to price, easiest to feel. Treatment gets delayed or substituted.

Here's the comparison that reframes the whole question. Take an ordinary item that costs you $40 and sells for $95, so $55 of margin:

	Cost
Carrying 5 extra units for a full year	$200 held × 25% = $50
Losing one single sale to an online pharmacy	$55

Carrying five extra units of that drug for an entire year costs you about the same as losing one fill. Not one client. One fill.

Which means the answer is per item, not per practice

Once you accept that the two costs are lopsided, and lopsided by different amounts for different items, a blanket policy stops making sense. "We're going lean this year" is not a strategy, it's a mood.

The actual control you have is the service level on each item, which is how confident you want to be that you won't run short. It's a dial, and it belongs at different settings on different shelves:

• A critical, hard-to-substitute drug. Push toward 99%. The extra cushion is cheap relative to what a gap costs you clinically and commercially.
• A commodity with three suppliers. Sit at 90%. A brief gap costs you almost nothing because you can replace it in an afternoon.
• A high-value item that barely moves. Lean, deliberately. This is where your money is actually trapped.

That dial is the input that turns into a cushion in the safety stock calculation, and the reason it's worth setting per item instead of once for the whole catalog.

Where the lean actually comes from

Here's the reframe that matters most, and the reason blanket cost-cutting so often fails.

Your trapped capital and your stockout risk almost never live on the same shelf.

Trapped capital accumulates in items you barely sell: the strength somebody ordered for one patient who moved away, the diet a rep talked you into, the duplicate SKU nobody noticed. These sit for a year, absorb carrying cost, and eventually expire.

Stockout risk lives in items you sell constantly: the drugs moving every week, where a small miscalculation shows up as an empty shelf within days.

So when a practice decides to "run leaner" and thins everything by the same percentage, it does the precisely wrong thing on both shelves at once. It barely touches the dead stock, because dead stock wasn't being reordered anyway. And it cuts into the buffer on exactly the fast-moving items where the buffer was doing real work.

Most practices find that the first project alone gets them where they wanted to be, without ever needing to take a risk on the second. If you want to find that money, start with how much cash is trapped on your shelves.

Numbers to steer by

Rather than a vague sense of "too much," a few benchmarks give you something to aim at:

• Inventory efficiency. Your inventory value as a percentage of monthly gross revenue. A commonly cited healthy band is 18% to 22%. Well above it and you're carrying too much. Well below it and you're likely running fragile.
• Inventory turnover. How many times a year you sell through your inventory value. 8 to 12 turns is a reasonable target for most general practices. Two turns a year means product is sitting for six months.
• Days of supply, per item. The most actionable of the three, because it's specific. An item with 300 days of supply is a decision you can make this afternoon.

Being under the band isn't automatically a win, which is the thing lean enthusiasm tends to forget. A practice running at 12% efficiency with weekly stockouts hasn't optimized anything. It has moved its costs somewhere that doesn't show up on the inventory line.

So how lean can you go?

Leaner than you are now, almost certainly. But not by the method most people reach for.

The honest answer is that "how lean" is the wrong question, because it assumes one number applies to a whole catalog. The better question is per item: what does being short of this specific thing cost me, and what does holding it cost me? Answer that and the right level falls out of the arithmetic. For most items you'll land leaner than today. For a handful of critical ones you'll deliberately land heavier, and you'll be right to.

That's not just-in-time. It's something more useful: right-amount-at-the-right-time, decided per item, with the clinical stakes actually priced in.

If you want the mechanics behind those per-item numbers, start with the reorder point for when to order and the economic order quantity for how much.