Veterinary drug · Drug monograph

Propentofylline: veterinary dose and monograph

Propentofylline is a veterinary drug. A xanthine-derivative vasodilator/rheologic agent (Vivitonin) licensed to improve DEMEANOUR and ACTIVITY in dull, lethargic OLDER DOGS — it increases cerebral and peripheral blood flow, improves red-cell flexibility (microcirculation) and… Indications include improvement of dullness/lethargy and exercise tolerance in older dogs (licensed); support of peripheral/cerebral microcirculation in geriatric patients; off-label: feline geriatric demeanour; equine distal-limb perfusion (laminitis/navicular adjunct). This monograph lists 1 reference dose for dogs, each with route, frequency and source.

At a glance

Drug class: Veterinary drug
Also known as: Vivitonin, Karsivan
Species with doses: Dogs
General dose range: 3–5 mg/kg PO q12h (before food) — check the species tables for the indication
Routes: PO
Last reviewed: 1 October 2026

Indications

Improvement of dullness/lethargy and exercise tolerance in older dogs (licensed)
Support of peripheral/cerebral microcirculation in geriatric patients
Off-label: feline geriatric demeanour; equine distal-limb perfusion (laminitis/navicular adjunct)

Propentofylline dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

Propentofylline doses for dogs
Indication	Dose	Route	Frequency	Duration
Geriatric dullness / activity / circulation	3–5 mg/kg	PO	q12h before food	—

Geriatric dullness / activity / circulation: Label-sourced — neither Papich 5e nor Plumb’s has a propentofylline monograph. Follow the Vivitonin/Karsivan label (twice daily on an empty stomach, at least 30 min before feeding).

Cats

Propentofylline doses for cats
Indication	Dose	Route	Frequency	Duration
No reference dose for this species	Not established in Papich 5e or Plumb’s 10e — do not extrapolate from another species	—	—	—

No reference dose for this species: No propentofylline monograph in Papich 5e or Plumb’s, and the product is labelled for dogs only.

Horses

Propentofylline doses for horses
Indication	Dose	Route	Frequency	Duration
No reference dose for this species	Not established in Papich 5e or Plumb’s 10e — do not extrapolate from another species	—	—	—

No reference dose for this species: No propentofylline monograph in Papich 5e or Plumb’s and no referenced equine dose.

Contraindications

Known hypersensitivity to xanthines. Significant cardiac arrhythmia / recent myocardial infarction-type events (xanthine cardiac stimulation). Bleeding disorders (anti-platelet effect). Caution in pregnancy. Severe hepatic impairment.

Adverse effects

Usually well tolerated
Occasional GI upset (vomiting), restlessness
Rare tachycardia (xanthine effect)

Drug interactions

Other vasodilators / antihypertensives: additive effects
Anti-platelet/anticoagulant drugs: additive bleeding tendency
Other xanthines (theophylline): additive cardiac/CNS stimulation

Pregnancy and lactation

Limited data; avoid in pregnancy unless clearly needed.

Monitoring

Demeanour/activity/exercise-tolerance response over days–weeks (owner-reported)
GI tolerance; heart rate if relevant
Investigate and treat any underlying disease causing the lethargy (it is supportive, not a cure)

Toxicity and overdose

Wide margin and well tolerated; overdose may cause GI upset, restlessness and xanthine-type cardiac stimulation (tachycardia). No characteristic organ toxicity at therapeutic use.

Management: No specific antidote. Supportive care; manage tachyarrhythmia/agitation if marked (as for xanthine effects). Effects are generally mild and self-limiting.

Clinical pearls

A nice "pick-me-up" for dull, slowing-down older dogs — improves cerebral/peripheral blood flow and often visibly lifts brightness, alertness and willingness to exercise
Give on an EMPTY stomach (≈30 min before food) for absorption; effect builds over days–weeks
Still work up the geriatric patient — rule out treatable causes of lethargy rather than just masking them
Mild anti-platelet/vasodilatory effects — use cautiously with other anticoagulants/vasodilators

Mechanism of action

A methylxanthine/phosphodiesterase-inhibiting agent that inhibits adenosine reuptake and phosphodiesterase, producing vasodilation and increased cerebral/peripheral/coronary blood flow; it also increases red-blood-cell deformability and inhibits platelet aggregation (improving microcirculatory flow) and has mild bronchodilator and anti-inflammatory/neuroprotective effects. The net result is improved tissue perfusion and oxygenation, which underlies the "brighter, more active" effect in older dogs.

Formulations and products

50 mg tablet (Vivitonin)
100 mg tablet
Vivitonin (MSD Animal Health) — 50 / 100 mg tablet, Tablet

Storage

Tablets: 15–30 °C, dry, protect from light.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Frequently asked questions

What is the dose of Propentofylline for dogs?

Reference doses for Propentofylline in dogs: 3–5 mg/kg PO q12h before food (Geriatric dullness / activity / circulation). Confirm against the label and the patient before use.

Can Propentofylline be given to cats?

Not established in Papich 5e or Plumb’s 10e — do not extrapolate from another species (No reference dose for this species).

Can Propentofylline be given to horses?