Why I Switched Our Clinic's Parasite Prevention from Lewis & Lincoln to Simparica (and What It Cost Us)

Let me paint you a picture. It's a Tuesday morning in February 2024, and I'm staring at an invoice that looks like it was printed on a receipt from 1995. Handwritten amounts, no tax breakdown, and the vendor code is literally 'LEWIS-01' – which nobody in our accounting system can match. I've spent the last hour on hold with a distributor trying to figure out if 'Lewis' refers to the manufacturer, the rep, or some third-party reseller.

This is the moment I decided we needed to change our flea, tick, and heartworm prevention protocol. Not because of efficacy – Lewis and Lincoln products worked fine for our patients. But because the process of getting them into our inventory was eating my team alive.

I'm the office administrator for a medium-sized veterinary clinic in the Midwest – about 15 staff members, 3 veterinarians, and we see roughly 200 patients a week. I handle all the purchasing for pharmaceuticals, which is about $80,000 annually across maybe 12 different vendors. I report to both the lead vet (Dr. Thompson) and the practice's financial director. And let me tell you, keeping them both happy is a balancing act that requires, among other things, impeccable record-keeping.

So when I started the process of switching our core parasite prevention from the established brands (Lewis and Lincoln) to Simparica, I knew I had to be meticulous. Here's how that played out—the good, the bad, and the unexpected lessons.

Our Old Setup: Lewis and Lincoln

For years, we relied on two mainstays: Lewis-branded flea/tick chews and Lincoln-based heartworm preventatives. They were what the vets were trained on, what the clients asked for by name, and what the local rep pushed. But from a purchasing standpoint, they were a nightmare.

The problem wasn't the drugs. It was the vendors.

We were ordering from three different distributors to get both lines. Lewis required a minimum order of $500 per shipment. Lincoln had a completely separate invoicing system that didn't integrate with our accounting software. Every month, I was reconciling manual invoices (which, honestly, sometimes had typos on the drug name—'Lewis' vs 'Luis' vs 'Lewi$'—I'm not kidding).

One time, in 2023, I placed an order for 300 doses of Lewis's chewable flea tablets. The distributor sent 300 doses of their generic version, which looked almost identical but had a different NDC code. We didn't catch it until a client called saying the tablets 'smelled different.' The client was upset (rightly so), and we had to do an emergency replacement. The whole thing cost us about $450 in wasted product, shipping, and a few hours of my time.

That was the straw that broke the camel's back. I told Dr. Thompson, 'We need a single-vendor solution for this.' And that's when I started looking seriously at Simparica.

The Switch to Simparica: The Research Phase

I'm not a veterinarian, so I'm not going to pretend I evaluated the clinical efficacy of Simparica against Lewis and Lincoln. That's Dr. Thompson's domain. My concern was operational: Could Simparica give us a simpler, more reliable, and more cost-effective supply chain?

I did my homework. According to Zoetis's official distributor list (accessed January 2024), Simparica is available through three major national distributors—MWI, AmerisourceBergen, and Patterson. That meant I could consolidate our ordering from three Lewis/Lincoln distributors down to one for Simparica. That alone was a huge win for my sanity.

But there was a catch. The pricing wasn't directly comparable. Lewis and Lincoln had rebate structures that were complicated—buy 12 boxes, get 1 free, but only if you hit a quarterly volume target, and only if you filed the paperwork within 30 days. Simparica had a simpler, net-based pricing model, but the per-unit cost was slightly higher. About 8% higher, based on the quotes I got in December 2023.

I presented this to the financial director. She asked, 'Is an 8% increase worth it for a simpler process?'

I said, 'What's more expensive: 8% on the drug, or the 6-8 hours a month I spend reconciling Lewis invoices and chasing down rebates?'

She didn't have an answer. I did. We moved forward.

The Transition: Three Months of Chaos (Thankfully)

The switch didn't happen overnight. We had to do a phased transition to avoid running out of stock. In January 2024, we stopped new orders of Lewis and Lincoln, but continued dispensing what we had in the fridge. The first Simparica order arrived in mid-February.

And then the real work began.

Staff Training – I assumed the vets and techs would just 'get it' since Simparica is a similar chewable format. Wrong. (Or rather, partially wrong.) The dosing schedule for Simparica Trio (heartworm, fleas, ticks) is different from Lewis's combination products. We had to create a crib sheet. We had three errors in the first week—one tech nearly dispensed a month's supply instead of a 3-month supply. (Thankfully, the prescription system caught it.)

Client Education – This was the biggest unexpected cost. Clients who had been using Lewis and Lincoln for years were skeptical. 'Why are you changing? Is Lewis not safe?' I had to field about 20 of these calls myself. Our front desk staff needed a script. We printed handouts (cost: about $0.50 each for 500 copies).

The 'Ah-Ha' Moment – It happened about six weeks in. A client came in, a regular with two golden retrievers. She'd been using Lincoln for years. She picked up her first Simparica dose and said, 'You know, this is the first time the invoice was right. No math errors, no missing manufacturer rebate. It just... worked.'

That's when I realized the switch wasn't just about saving my time. It was about client trust. A mistake in invoicing or product consistency erodes the client's confidence in the clinic. If we can't get the medicine right, how can they trust us with their pet's health?

And that ties directly into the brand image. The quality of our supply chain—the accuracy of our invoicing, the consistency of our product—is a direct reflection on the clinic's professionalism. When I switched to Simparica, client feedback scores improved measurably. In Q2 2024, our satisfaction survey scores related to 'ease of picking up prescriptions' went up by 18% compared to Q4 2023.

The Numbers, Six Months In

As of July 2024, here's the breakdown:

• Vendors: Reduced from 3 to 1 (for this line of products).
• Monthly admin time on this category: Down from ~7 hours to ~1.5 hours—a savings of 5.5 hours monthly. At my effective hourly rate, that's about $1,100 in saved labor over 6 months.
• Product cost: Up about 7.5% (the 8% was close but I'm rounding down because of some volume discounts we negotiated). Cost us an extra $1,800 over 6 months.
• Net financial impact: Negative $700. But the hidden savings? No more reconciling bad invoices. No more emergency re-shipments. No more angry clients.

Was it worth it? Absolutely. The financial cost was minimal compared to the operational relief. And the improvement in client perception—that's the part you can't put a dollar sign on, but it's the most valuable outcome.

Lessons Learned for Anyone Making a Similar Switch

If you're an administrator thinking about changing your clinic's core pharmaceutical supplier—whether from Lewis, Lincoln, or any other brand—here's what I wish someone had told me:

1. Don't underestimate the training cost. I budgeted for the price difference. I did not budget for the 20 hours I'd spend training staff and creating new protocols. Budget 40 hours of admin time for the transition.
2. The switch will expose your weak points. Our drug inventory system was held together with spreadsheets and hope. The switch forced us to digitize properly (which we should have done years ago).
3. Client communication is non-negotiable. I wrote a short letter explaining the change (focused on 'improved consistency and simpler process,' not 'the old vendors were a nightmare'). We emailed it and put a copy in every patient's pickup bag for the first month. It cut questions by 60%.
4. Pick one vendor and build a relationship. The simplicity of dealing with a single, professional distributor (in our case, MWI) is worth the 8% premium. I can call one person, get a consistent invoice, and not waste my time on the phone chasing down errors.

There's something satisfying about a perfectly executed supply chain. After the stress of the Lewis and Lincoln years—the manual invoices, the product mix-ups, the look on Dr. Thompson's face when I had to tell him we'd run out of a core drug—finally having a system that works is the payoff. No more 3am worry sessions about whether the order will arrive. No more explaining to the financial director why we have a $400 expense that doesn't match any purchase order.

The best part? A client the other day said, 'You guys are so organized. I never have to follow up on anything.' That's the goal. That's why we made the switch.

Pricing referenced in this article is from quotes obtained from MWI Animal Health, AmerisourceBergen, and Patterson Veterinary in December 2023 and January 2024. Actual pricing may vary. Verify current pricing with your distributor.