Dormosedan Gel for Horses: Dosage Chart, Free Calculator, Onset Time & Safety Rules Every Owner Should Know

Written & Reviewed By: Medshorse Team
Last Updated: October 2026

Dormosedan gel for horses is a prescription sedative you squirt under the tongue, not down the throat. The FDA-approved label sets the dose at 0.018 mg per pound (0.040 mg/kg), which means 1.00 mL for a 330–439 lb horse and up to 3.00 mL for horses between 1,210 and 1,320 lb. A typical 1,000 lb horse gets 2.50 mL.

If you have ever tried to wrap a leg on a horse that won’t stand still, held a nervous gelding for the farrier, or sat through fireworks night with a horse spinning in the paddock, you already know why owners ask their vets about “dorm gel.” It lets you calm a healthy horse for non-painful jobs without a vet on the farm.

It is also easy to get wrong. The gel needs about 40 minutes to work, it must go under the tongue, it does nothing for pain, and handlers need gloves. This guide gives you the full dosage chart, a free calculator, step-by-step instructions, timing, side effects and safety rules, all taken from the label and Zoetis’ own product information, which we checked in October 2026.

Disclaimer: This article is for general education and is not veterinary advice. Dormosedan is a registered trademark of Orion Corporation, distributed by Zoetis under license. MedsHorse is not affiliated with Zoetis. Always follow your veterinarian’s instructions and the current product label.

What Is Dormosedan Gel for Horses?

Dormosedan Gel (detomidine hydrochloride) is an oromucosal gel that sedates horses when absorbed through the lining of the mouth. Each mL holds 7.6 mg of detomidine HCl, and it comes as a blue gel in a 3 mL graduated oral syringe. The FDA approved it under NADA 141-306, and Zoetis distributes it in the US.

The label lists it for “sedation and restraint in horses.” In plain language, Zoetis describes it as a mild standing sedative that horse owners can give before non-painful procedures or stressful situations when a vet isn’t there. The company stresses that it should be used in healthy horses and prescribed in advance by your veterinarian.

How Dormosedan Gel Works

Detomidine is an alpha-2 adrenoceptor agonist. It dampens the nerve signals that keep a horse alert, so the head drops, the front legs plant in a wide stance and the horse reacts less to its surroundings.

The drug also changes how the body behaves. Blood pressure rises at first, then settles, while heart rate drops sharply. Gut movement slows, blood sugar rises, and urine output increases two to four hours after treatment. Those are normal drug effects, and they are why the label lists so many cautions.

Absorption is the key difference from an injection. The label reports 22% bioavailability and peak blood levels about 40% of those after an intramuscular injection. Almost nothing reaches the bloodstream if the gel is swallowed, which is why placement under the tongue matters.

How Much Dormosedan Gel For Horses?

The label dose of Dormosedan Gel for horses is 0.018 mg per pound, or 0.040 mg/kg, given sublingually. The syringe delivers in 0.25 mL steps, so the volume runs from 1.00 mL for horses of 330–439 lb up to 3.00 mL for horses of 1,210–1,320 lb. Use the chart below, then confirm with your vet.

Dormosedan Gel Dosage for Horses Calculator

Dormosedan Gel Dosage Chart for Horses (By Weight)

Approx. body weight (lb)	Approx. body weight (kg)	Dose volume	Detomidine HCl (calculated)
330–439 lb	150–199 kg	1.00 mL	7.6 mg
440–549 lb	200–249 kg	1.25 mL	9.5 mg
550–659 lb	250–299 kg	1.50 mL	11.4 mg
660–769 lb	300–349 kg	1.75 mL	13.3 mg
770–879 lb	350–399 kg	2.00 mL	15.2 mg
880–989 lb	400–449 kg	2.25 mL	17.1 mg
990–1,099 lb	450–499 kg	2.50 mL	19.0 mg
1,100–1,209 lb	500–549 kg	2.75 mL	20.9 mg
1,210–1,320 lb	550–600 kg	3.00 mL	22.8 mg

Dose volumes are from Table 1 of the Dormosedan Gel label. The milligram column is our arithmetic: mL × 7.6 mg/mL.

Common Dormosedan Gel Doses by Horse Size

• 500 lb horse (small pony-sized or light horse): 440–549 lb band, 1.25 mL. The label hasn’t evaluated ponies, so ask your vet.
• 800 lb horse: 770–879 lb band, 2.00 mL.
• 1,000 lb horse: 990–1,099 lb band, 2.50 mL.
• 1,200 lb horse: 1,100–1,209 lb band, 2.75 mL.
• 1,300 lb horse: 1,210–1,320 lb band, 3.00 mL, the full syringe.

What If Your Horse Is Outside the Chart?

The chart covers 330 to 1,320 lb (150 to 600 kg). Horses outside that range, ponies, miniature horses and animals under one year are not covered by the label. Your veterinarian has to decide whether the gel is appropriate at all. Don’t estimate a dose yourself.

Why Accurate Weight Matters

Each band on the chart covers about 110 lb, so a weight tape that is off by a hundred pounds can push a horse into the wrong band. The label’s dose ranges show that horses at the bottom of each band get slightly more than 0.040 mg/kg and horses at the top slightly less. Zoetis recommends a weight tape or scale. A scale is better when you can get one.

Can You Give a Second Dose?

No. The label states that repeat dosing has not been evaluated, and Zoetis’ client sheet tells owners not to repeat the dose. If your horse isn’t sedated after 40 minutes, call your prescribing veterinarian. You may be dealing with a swallowed or spat-out dose, an excited horse, or a horse that doesn’t respond well to detomidine.

How to Give Dormosedan Gel to a Horse (Step by Step)

Give Dormosedan Gel with the horse’s mouth empty, food and water removed, and gloves on. Set the ring to the prescribed volume, place the tip under the tongue at the corner of the mouth, press the plunger fully, then leave the horse alone in a quiet spot for at least 40 minutes.

Common Mistakes to Avoid

Tips From the Label and Zoetis for Better Results

How Long Does Dormosedan Gel Take to Work and How Long Does It Last?

Plan on about 40 minutes for Dormosedan Gel to take effect and approximately 90–180 minutes of sedative effect. Recovery can take 3 to 4 hours. By comparison, the injectable form begins working in 2–4 minutes IV or 3–5 minutes IM, so the gel demands more patience.

In the label’s field study, 94% of gel-treated horses showed minimal, moderate or marked sedation at 40 minutes, versus 14% on placebo. Mild swaying was seen in 54% of treated horses at that point and moderate ataxia in 25%. For a small share, moderate to marked ataxia lasted longer: 5% at 90 minutes and 4% at 120 minutes.

Those numbers are why Zoetis calls it a “standing” sedative but still warns about unpredictable behavior. A swaying horse can lose its balance, and a sedated horse can still kick.

Why Some Horses Don’t Seem to Respond

The label explains that nervous or excited horses have high levels of natural adrenaline, which can reduce the effect of drugs like detomidine. Onset may be slow, and the depth and duration can be reduced or absent.

That is one reason to give the gel in a calm setting well ahead of time rather than as a last resort for a horse already in a panic.

What Is Dormosedan Gel Used For?

Zoetis lists farrier work, bandaging, basic first aid, fireworks, first-time supervised turnout of fractious horses on a dry lot, mane pulling, body clipping and sheath cleaning. All are non-painful, routine tasks where an anxious horse might otherwise be unsafe for itself and its handler.

The field study also shows where the gel helps most. It worked well for manual teeth floating, hoof care and prepuce cleaning, and least well for electric clipping, where only 48% of horses were successfully handled.

If your horse panics at clippers, ask your vet whether the gel is enough or whether a vet-administered plan makes more sense.

What Dormosedan Gel Is Not For

Dormosedan Gel doesn’t relieve pain. The label says plainly not to use it for painful procedures, and Zoetis says it is intended for healthy horses. That rules out sedating a horse that is colicky, lame or in pain to “take the edge off.” Pain needs a diagnosis and a different plan.

Our guides to Banamine dosage for horses and bute dosage for horses explain how those prescription pain medications are dosed, but the choice and the dose should always come from your vet, especially when the horse is hurting.

Dormosedan Gel Side Effects in Horses

The most common side effects in the label’s field study were sweating (about 10% of gel-treated horses), penile relaxation (6%), a very slow heart rate of 20 beats per minute or less (5%), second-degree AV block (4.5%) and frequent urination (4.5%). None of these appeared in the placebo group.

Reaction	Gel-treated horses (of 202)	Share	Placebo horses (of 68)
Sweating	20	9.9%	0
Penile relaxation	12	5.9%	0
Bradycardia (20 bpm or less)	11	5.4%	0
Second-degree AV block	9	4.5%	0
Frequent urination	9	4.5%	0
Piloerection (raised hair)	4	2.0%	0
Marked ataxia	3	1.5%	0
Facial or oral edema	3	1.5%	0
Hypersalivation	2	1.0%	0
Nasal discharge	2	1.0%	0
Flatulence	1	0.5%	0
Epiphora (tearing)	1	0.5%	0
Pale mucous membranes	1	0.5%	0
Swollen sheath	1	0.5%	0
Muscle tremors	1	0.5%	1

Adverse reactions in the US field study. Percentages are our calculation from the label counts.

Heart and Blood Pressure Effects

Detomidine slows the heart and can cause heart block. In the target-animal safety study at the label dose, ECGs showed increased vagally mediated arrhythmias in most horses, with no clinical abnormalities linked to them.

Even so, the label contraindicates the gel in horses with pre-existing AV or SA block and warns against use in horses with cardiovascular disease.

Other Effects You May Notice

• Head lowering with possible nasal discharge and temporary swelling around the face and eyes
• Sweating, salivation and slight muscle tremors
• Reduced gut motility and higher blood sugar
• Increased urination 2–4 hours after treatment
• Reddened mucous membranes where the gel was placed (seen in 2 of 8 horses in a lab study, and 2 of 6 in the safety study)

When to Call Your Vet Right Away

• The horse is still not sedated after 40 minutes, or you think the dose was swallowed or spat out
• Marked staggering, collapse, trouble breathing or facial swelling
• Severe sweating, tremors or a very slow, irregular heartbeat
• The syringe malfunctioned and you aren’t sure how much was given
• Any reaction that worries you

You can also report adverse reactions to Zoetis at 1-888-963-8471 or to the FDA at fda.gov/reportanimalae.

Dormosedan Gel Safety: Who Should Not Get It

Don’t use Dormosedan Gel in horses with known detomidine hypersensitivity, AV or SA block, respiratory disease or chronic kidney failure. The label also warns against use with cardiovascular, liver or kidney disease, shock, severe debilitation, or stress from extreme temperatures, fatigue or altitude. It is not for painful procedures.

Drug Interactions

The label says not to use the gel with other sedative drugs because the effects may be additive. Intravenous potentiated sulfonamides must also be avoided in sedated horses, since potentially fatal dysrhythmias may occur. If your horse takes any antibiotic, such as the combinations covered in our guide to sulfadiazine trimethoprim, tell your vet before you plan a sedation day.

If you’re comparing calming options, our guides to acepromazine and the trazodone explain those drugs separately. Don’t combine any of them with Dorm Gel unless your vet gives you instructions.

Handler Safety

Detomidine can be absorbed through your skin, eyes and mouth. After dosing, treated horses carry small amounts in saliva: up to 0.072 mg/mL at 30 minutes, under 1% of the gel’s concentration, and below 0.010 mg/mL by two hours. That is why Zoetis tells handlers to use gloves for any mouth contact for at least two hours.

Dormosedan Gel vs. Injectable Dormosedan

Both products contain detomidine hydrochloride, but they are used very differently. The gel is a milder, slower, owner-administered sedative with no analgesia claim. The injectable is a stronger vet-administered sedative and analgesic. For the injectable, see our Dormosedan injectable for horses.

Feature	Dormosedan Gel	Dormosedan injectable
Concentration	7.6 mg/mL	10 mg/mL
Route	Under the tongue (sublingual)	Intravenous or intramuscular
Label dose	0.040 mg/kg (0.018 mg/lb)	20 or 40 mcg/kg (0.2 or 0.4 mL per 100 kg)
Who gives it	Owner or handler, with a vet prescription	Veterinarian
Onset	About 40 minutes	2–4 min IV, 3–5 min IM
Sedation duration	About 90–180 minutes	30–90 min (20 mcg/kg), about 90 min–2 hr (40 mcg/kg)
Pain relief	None shown. Not for painful procedures	Labeled as a sedative and analgesic
Packaging	Single 3 mL oral syringe	5 mL and 20 mL multidose vials

Sources: Dormosedan Gel label (DailyMed) and Zoetis Dormosedan Dosing Reference Guide.

Dormosedan Gel Price, Prescription and Storage

Expect to pay about $30 for one 3 mL syringe. In October 2026, Chewy, Tractor Supply and PetSmart each listed it at $30.72, and one veterinary supplier listed a 10-pack at $300.72. A prescription is required, and your vet’s own pricing may differ.

Item	What to know
Prescription	Required. Zoetis says you need an established client relationship with a veterinarian.
Typical price	About $30.72 per 3 mL syringe at major online pharmacies (October 2026). Prices change.
One syringe covers	Any horse in the label chart, up to 1,320 lb (600 kg).
Storage	Original package, 20–25°C (68–77°F). Excursions to 15–30°C allowed.
Leftovers	Don’t reuse partially used syringes. Ask your vet how to discard them.
Who it’s for	Only the horse it was prescribed for.

Keeping It in Your Horse First-Aid Kit

Zoetis encourages owners to keep a syringe or two in the equine first-aid kit for bandage changes, hoof care and minor non-painful procedures. Talk to your vet about it before you need it. A calm horse in good health on a quiet day is far easier to plan around than an injured, panicking horse at midnight.

Using It Before Horse Shows or Racing

Rules vary, and many governing bodies restrict sedatives. The label does not give a competition withdrawal time, so check your association’s medication rules and ask your vet before dosing a horse that will compete.

Checklist: Before You Open the Syringe

• You have a current prescription for this horse from your vet
• The horse is healthy, adult and within 330–1,320 lb (150–600 kg)
• The job is non-painful, and you have not given any other sedative
• You weighed the horse with a tape or scale and checked the dose volume
• Impermeable gloves are on and food and water are removed
• The horse is calm, the mouth is empty and you have a quiet place to wait at least 40 minutes
• You know your vet’s number and the Zoetis adverse reaction line, 1-888-963-8471

Key Takeaways

• Dormosedan Gel is detomidine HCl at 7.6 mg/mL, dosed at 0.018 mg/lb (0.040 mg/kg) under the tongue.
• The label chart runs from 1.00 mL (330–439 lb) to 3.00 mL (1,210–1,320 lb) in 0.25 mL steps.
• Wait at least 40 minutes. Sedative effects last roughly 90–180 minutes, with recovery taking up to 3–4 hours.
• It gives no pain relief, so it’s the wrong tool for colic, lameness or painful procedures.
• Don’t repeat the dose, and don’t combine it with other sedatives without your vet.
• Handlers need impermeable gloves and extra caution for at least two hours after dosing.
• A sedated horse can still kick, so stay alert and keep the environment quiet.

Good horse care is mostly planning, which is what any qualities of a good horse owner does: talk to your vet early, have the right dose written down, and set up a calm day instead of reacting in a crisis.

FAQs

Sources and Further Reading

• Dormosedan Gel label, DailyMed (FDA-approved prescribing information)
• Dormosedan Gel product page, Zoetis Equine
• Dormosedan Gel client information sheet for owner/handler use and safety, Zoetis
• Dormosedan dosing reference guide (injectable), Zoetis
• Report an animal drug adverse event, FDA