Vetoquinol Zylkene Calming Support Supplement for Large Dogs 33-132lbs
- Calming Aid
- 169.1 fl oz
- Dog
- 1
A milk-protein-derived calming capsule dosed for large dogs, aimed at situational stress like moving or storms rather than daily sedation.
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How it ranks among the 63 calming aids we track
3.9★ across 1,000 Amazon ratings, Bayesian-smoothed toward the category average.
1,000 Amazon ratings, weighted on a log scale so huge counts don't drown everything.
400+ bought on Amazon last month.
Brand identity, imagery, description and spec coverage.
The ProductDome score is separate from the Amazon rating shown above: it combines the Bayesian-smoothed Amazon rating with evidence volume, tracked demand, and data quality across the 63 calming aids we track - how the scorecard works · full calming aids data report. Confidence: high - strong rating volume and complete data.Last refreshed Aug 4, 2026. Data-computed, not a hands-on test. Compiled by the ProductDome Research Team.
Overview
A calming capsule for large dogs between 33 and 132 pounds, built on alpha-casozepine derived from milk protein, sold as 30 capsules at 450mg each.
Zylkene's active ingredient is alpha-casozepine, sourced from bovine milk protein, positioned as an alternative to melatonin-based calming products. Vetoquinol markets it for stress tied to moving, travel and thunderstorms, not just general anxiety. The capsule is flavorless and sized specifically for the 33 to 132 pound weight range.
- 30 capsules, 450mg each
- For large dogs, 33-132 lbs
- Alpha-casozepine, milk protein derived
- Targets moving, travel, thunderstorm stress
Who it's for
Owners of large dogs facing a specific stressor, a move, storm season, or travel, who want a milk-protein-based calming option rather than melatonin. Not sized for small or medium dogs given the 33-pound minimum.
Strengths and trade-offs
Drawn from this product's published specifications.
- Alpha-casozepine active ingredient, milk-protein derived
- Dosed specifically for large dogs, 33-132 lbs
- 30-count supply lasts about a month at daily dosing
- Not sized for small or medium dogs
- Rating sits slightly lower at 3.9
- No owner reviews yet
Performance notes
The formula's calming action comes from alpha-casozepine rather than melatonin, and Vetoquinol frames it around discrete stress events like relocation or thunderstorms. At 30 capsules for a daily-use product, the supply covers roughly a month before reordering.
Specifications
| Brand | Vetoquinol |
|---|---|
| Model | Zylkene Caps 450 |
| Dimensions & fit | |
| Item Weight | 0.8 ounces |
| Dog Breed Size | Large |
| Capacity & performance | |
| Volume | 169.1 fl oz |
| Included components | |
| Unit Count | 30 |
| Included Components | Vetoquinol Zylkene 450mg (30 capsules) |
| Other details | |
| Pet Type | Dog |
| Number Of Items | 1 |
| Best Sellers Rank | #10,516 in Pet Supplies (See Top 100 in Pet Supplies) #110 in Dog Relaxants |
| Product Benefits | Calming Support |
| Active Ingredients | Hydrolized milk protein (bovine) providing alpha-casozepine, FD&C blue #1 (capsule), hypromellose (capsule), magnesium stearate, maltodextrin, titanium dioxide (capsule) |
| Model Number | Zylkene Caps 450 |
| Upc | 017030340853 615867813269 |
| Flavor | Flavorless |
| Manufacturer Part Number | Zylkene Caps 450 |
| Asin | B00GSWIKOC |
| Item Form | Capsule |
| Manufacturer | Vetoquinol |
| Specific Uses For Product | anxiety, moving, stress, thunderstorms |
| Customer Reviews | {'ratings_count': '1,005', 'stars': '3.9'} |
| Target Species | Dog |
Other Vetoquinol calming aids
How it compares
This product against the closest alternatives we track in calming aids.
| Product | Amazon rating | Ratings | ProductDome score |
|---|---|---|---|
| Vetoquinol Zylkene Calming Support Supplement for Large Dogs 33-132lbsThis product | 3.9 / 5 | 1,000 | 3.9 / 5 |
| ThunderShirt for DogsThunderShirt | 4.2 / 5 | 55,700 | 4.3 / 5 |
| Rescue Remedy Pet DropperRescue | 4.2 / 5 | 19,500 | 4.3 / 5 |
| Advanced Calming Chews for DogsAdvanced | 4.4 / 5 | 2,500 | 4.4 / 5 |
| Zesty Paws Calming Chews for Dogs Composure & Relaxation for Everyday Stress & Separation…Zesty | 4.1 / 5 | 26,600 | 4.3 / 5 |
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Questions about the Vetoquinol Zylkene Caps 450
Common buyer questions answered straight from the product spec data - no fluff, no "it depends".
What is alpha-casozepine?
It is a compound derived from bovine milk protein that Vetoquinol uses as the calming active ingredient in Zylkene.
What weight range is this sized for?
It is formulated for large dogs between 33 and 132 pounds.
How long does one box last?
The box contains 30 capsules, which covers about a month at one capsule per day.