How to Shop for Calming Supplements 

Does looking at the number of calming supplements available make you want to spin and bolt? Don’t shy away just yet! We’re here to help you choose the ideal calming formula for your horse so that you can be confident in your decision and your horse can be confident on your rides.
There are three types of calming supplements to choose from: nutrient-based formulas, herbal formulas, and herbal formulas designed specifically for moody mares. Here we’ll take a look at these three types of supplements and get a better understanding of how the ingredients in each work, so you can find the right support for your horse.

Nutrient-based Calming Supplements

How they work:

As “nutrient-based” suggests, calming supplements in this category provide nutrients that are already a part of your horse’s diet. Horses that aren’t getting enough of the key nutrients necessary for nervous system function may be anxious, edgy, or reactive so these formulas are designed to bring your horse’s levels into the optimal range for a properly functioning nervous system.

Key ingredients to look for:


A key player in nervous system function, magnesium is a macro-mineral that serves as an activator of hundreds of enzymes, and as a participant in muscle contractions. Your horse should be getting magnesium from his basic diet, but because horses in moderate to heavy work have additional requirements for magnesium, it may not be enough. Supplementing your horse with magnesium can give his body what it needs to help the nervous system function properly. Because one of the clinical signs of magnesium deficiency is nervousness, many riders find that their horses have a balanced temperament and are able to stay focused when supplemented with magnesium. 
Magnesium has maximum tolerable concentration estimated at 0.8% of the diet (80 g or 80,000 mg for an 1100 lb horse) and you’ll most often find supplements in this category containing between 500-16,000 mg. These amounts are generally appropriate to be added on to a horse’s otherwise balanced diet. Typically, 500-2,000 mg is considered to provide basic support while higher levels may be a better choice if you are looking for more comprehensive support.

Vitamin B1:

Also known as thiamine, vitamin B1 is important in the normal transmission of impulses along nerves. The National Research Council has set dietary requirements for vitamin B1 in horses because, unlike with most B-vitamins, the microorganisms in the hindgut don’t make enough thiamine to meet a horse’s needs. That means that your horse needs to consume B1 in his diet in order to receive an adequate amount. Pasture and grain are a good source of this vitamin, but horses in work and those who don’t have access to fresh pasture or aren’t fed fortified grain may not be getting enough.

Supplementing with vitamin B1 will help ensure that your horse is getting enough for his nervous system to function normally. While higher or lower amounts may be appropriate depending on your horse and the level of support you’re looking for, you’ll generally find between 500 – 2,000 mg of vitamin B1 in most calming supplements.



A close relative of the B-vitamin family, inositol is found in nearly every cell in the body. One of its major roles is assisting in nerve transmission. By participating in the action of serotonin, a neurotransmitter that produces feelings of well-being and contentment, inositol may be helpful for excessively nervous horses. It can be found in calming supplements at the level of 1,000 – 2,000mg.



An essential amino acid, tryptophan is a critical protein building block that must be supplied in the horse’s diet, similar to vitamin B1. Tryptophan is converted by the body into serotonin, leading to proper levels of this hormone that acts within the brain to soothe and content. Levels between 500 – 2,500 mg support horses with excess anxiety.

What to Expect from Nutrient-based Calming Supplements:

The timeline will vary from horse to horse, but you may be starting to see signs of your horse staying relaxed and attentive within the first few weeks or so. If not, that’s okay, for some horses it can take 4-6 weeks for this type of supplement to reach its full benefit. The ingredients should continue to help support a nervous system over the next couple of weeks, so that you both can get the most out of your rides going forward.


Horses that may benefit from a Nutrient-based Calming Supplement include:

Supplements in this category are an ideal starting point for any horse that is nervous, edgy, reactive, unconfident, or spooky. By supplying the nutrients needed for proper nervous system function and observing the results, you may be able to determine if your horse’s nervousness is because there aren’t high enough levels of a core element of his diet.
Additionally, if you compete in rated horse shows, nutrient-based supplements are your only option. Herbal calming supplements include ingredients that are forbidden by many competitive organizations, but the ingredients in nutrient-based formulas are key nutrients like tryptophan, magnesium, and B-vitamins that are already in your horse’s diet.

Shop All Calming Supplements

Herbal Calming Supplements

How they work:

As the name suggests, the formulas in this type of calming supplement include herbal ingredients. Like the ingredients in nutrient-based supplements, the ingredients in herbal calming formulas are beneficial because of their effect on the nervous system.

Key ingredients to look for:


This potent herb helps balance a nervous system struggling with excess anxiety. It can also help address muscle cramps and spasms associated with tension, so it’s especially helpful for horses that hold their anxiety in their muscles and get tense. Depending on the amount of support you’re looking to provide, around 50-2,500 mg of valerian may be a great addition to your horse’s program.


Another herb with specific support for the nervous system. It is especially helpful for horses that process their nervousness through their gastrointestinal system (you know, that horse in your barn with the “nervous tummy”). Anywhere from 200 – 2,000 mg of chamomile may add support.


This herb has been used for centuries to help alleviate nervous tension, anxiety, irritability, and other disturbances related to the nervous system. In horses, it’s helpful for those that are prone to “mental anxiety” and become distracted and unfocused. Around 1,500 mg of hops is generally considered a good amount of support.


This herb may help balance the nervous system of horses who have excess energy, helping them concentrate on the job at hand. You’ll most often see between 100-750 mg of vervain in herbal calming supplements that include this ingredient.

Passion flower:

This herb supports a calm and relaxed disposition. It appears to be particularly helpful when used together with valerian, chamomile, hops, or vervain. Around 150 mg of passion flower will provide calming support.

What to expect from Herbal Calming Supplements:

Herbal ingredients for nervous system health can take time to reach their full benefit, generally about 4-6 weeks. Over the first few weeks look for signs that your horse is able to focus on the job at hand, allowing you both to have more fun doing what you love. We also recommend observing your horse during events or times that would have previously caused him stress and watch for him to keep his cool.


Horses that May Benefit from a Herbal Calming Supplement include:

If you don’t compete in rated horse shows (products in this category contain herbs not permitted by many competitive organizations), an herbal calming formula is a great option to consider. Additionally, if you’ve tried a nutrient-based supplement and didn’t see the results you were hoping for, switching your horse to an herbal formula may be an appropriate next step. Finally, if you’re currently feeding a nutrient-based supplement and you like what you’re seeing but still want to provide more support, pairing your nutrient-based formula with an herbal formula may be an appropriate choice for your horse.

Shop All Calming Supplements

Moody Mare Supplements

How they work:

If your sweet mare turns into a moody monster in or around her heat cycle, her poor attitude could be related to hormonal fluctuations or discomfort in her reproductive and digestive tracts. In addition to any of the herbs listed in the previous section, a formula designed for a temperamental mare will likely include ingredients that support balanced hormones and an even disposition. 

Key ingredients to look for:


The active ingredients in this herb support normal smooth muscle tone in both the reproductive and digestive tracts, helping it stay relaxed. Supplements will range from 800 – 5,000 mg of this herb, which is the most popular herb in this category.


Vitex agnus castus:

Also known as chaste berry, this herb helps maintain a balanced hormonal system. 100-500 mg of chasteberry may be provided, with higher levels being a good option for more comprehensive support.


Cramp bark:

Just as the name implies, cramp bark may help to maintain healthy reproductive muscles in mares who are prone to cramping. This can help them stay comfortable and maintain a happy demeanor.

When choosing a calming supplement for your mare, keep in mind that some of the herbal ingredients in many moody mare supplements are forbidden by competitive organizations.

What to Expect from Mare Supplements:

Mare supplements also generally take 4-6 weeks to see the full benefits. Over the first couple of weeks, watch for your mare to show off her pleasant temperament now that she’ll be getting ingredients to support healthy hormone levels. We also recommend proactively talking with your veterinarian about an appropriate management plan for her.


Horses that May Benefit from a Mare Supplement Include:

Mares who struggle to stay comfortable, or to maintain their normal demeaner during their heat cycle, or who could use support to maintain normal hormone levels may be the perfect candidates for this type of support. 
Shop All Mare Supplements

Need help deciding? Our smarts are at your service!

If you’re still not sure which supplement would be ideal for your horse, don’t fret - our Horse Health Experts are here for you! Just give us a call at 1-800-461-8898, text us at 26756, or live chat with us at, and we’d be happy to help you choose the perfect calming supplement for your horse.

If you’re managing active behavioral issues, we also recommend working with a trainer that you trust to help pinpoint where your horse may be struggling and to come up with the best plan going forward, which may include support from an appropriate calming supplement!

SmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.