Trichlormethiazide/Dexamethasone Paste

Paste medications are thick and sticky, usually given by mouth using a syringe or tube. They’re often used for dewormers or other oral meds in horses, dogs, and cats. The key is to aim for the back of the mouth so your pet swallows the paste instead of spitting it out.

For Horses:

1. Set the dose on the syringe if it has markings (usually based on weight).
2. Stand beside your horse, not in front, and have someone hold them if possible.
3. Gently insert your thumb into the side of the horse’s mouth (between the teeth) to open it.
4. Insert the syringe into that gap and squirt the paste toward the back of the tongue.
5. Lift the horse’s head slightly and encourage swallowing by stroking the throat or gently blowing on the nostrils.
6. Watch for licking or chewing—that means they swallowed. If paste spills out, check how much was lost and contact your vet if unsure.
7. You can offer a little water afterward and reward them with a treat like a carrot if allowed.

For Dogs & Cats:

1. Gently open your pet’s mouth or slip the syringe into the side of it.
2. Aim toward the back of the tongue and squirt the paste in.
3. Hold the mouth closed briefly, and rub the throat or blow gently on the nose to encourage swallowing.
4. Give praise or a treat afterward to make it a positive experience.

Aftercare:

1. Wipe your pet’s mouth if needed.
2. Clean or recap the syringe as instructed.
3. Store the tube according to label directions.

Tip: Paste can feel weird to pets at first. For horses, try giving applesauce by syringe ahead of time so they get used to the sensation.

This compounded formulation combines trichlormethiazide, a diuretic, with dexamethasone, a corticosteroid—two different drug classes. In compounding practice, clinicians may consider a combination like this to address fluid accumulation and inflammation together. Your veterinarian determines whether it is appropriate based on your animal's status.

At a pharmacological level, the two ingredients act through independent mechanisms. Trichlormethiazide is a diuretic that inhibits the reabsorption of sodium and chloride in the distal convoluted tubules of the kidney, facilitating the excretion of water and electrolytes. Dexamethasone is a glucocorticoid that binds to cytoplasmic receptors and modulates gene expression, reducing pro-inflammatory mediators and influencing capillary permeability. Together, the two ingredients act on fluid balance and inflammation through complementary mechanisms.

This description reflects the general pharmacology of the active ingredient's drug class; your veterinarian determines whether this approach is appropriate for your animal.

Prescription only. Use only under the direction of a licensed veterinarian. This information is not a substitute for veterinary diagnosis, prescribing or monitoring. Compounded drugs are not approved by the FDA for safety or effectiveness.

Commonly observed effects of trichlormethiazide/dexamethasone include increased thirst (polydipsia) and more frequent urination (polyuria), which are expected physiological responses to the diuretic and corticosteroid components. In some horses, glucocorticoids have been discussed in the context of a hoof condition and your veterinarian will monitor for any signs of hoof sensitivity. Owners should also watch for transient gastrointestinal changes or shifts in appetite. If you observe significant behavioral changes, persistent muscle weakness or signs of acute physical distress, contact your veterinarian promptly.

This medication is typically used with extra caution or avoided in patients with known kidney or liver impairment, as well as those with significant electrolyte imbalances. It is also carefully evaluated in pregnant animals, as dexamethasone can influence the timing of parturition in certain species. Because both components can interact with other prescriptions, including non-steroidal anti-inflammatory medications (NSAIDs) and certain heart medications, providing your veterinarian with a complete history is essential. Your veterinarian will monitor your animal's response to ensures the protocol remains suitable for their individual health status and will provide guidance on hydration management during the administration period. Both trichlormethiazide (a diuretic) and dexamethasone (a corticosteroid) are subject to detection in equine medication-testing programs and diuretics are commonly classified as prohibited substances by many governing bodies. Withdrawal times vary by jurisdiction; consult your veterinarian and the applicable governing body well in advance of any event.