Cyclosporine
Cyclosporin A
Also known as: Optimmune · Restasis · Atopica · Cyclavance · Modulis · Sporimmune · Cyclosporin A · Ciclosporin · Cyclosporine
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Audited v13 dosing evidence
Structured calculator evidenceAllergic dermatitis (extra-label)
Verified clinician required
- q24-48h
NA
Governing clinical context (3)
- NOTE: Dosages are for cyclosporine (modified), Atopica®, Cyclavance®, Neoral®, or equivalent; these dosages are not interchangeable with Sandimmune® (or equivalent) dosages.
- ■ Consider therapeutic drug monitoring (pharmacokinetic and pharmacodynamic) to assess effectiveness of therapy, particularly when response is poor or when adverse effects occur. Therapeutic drug monitoring can also be considered when changing brands or manufacturers, especially if response to therapy changes in the individual patient. Cyclosporine blood concentrations are not typically monitored when treating atopic dermatitis 93 or inflammatory bowel disease 9 because the blood concentrations were found to not correlate with clinical efficacy, but this may be warranted in some cases. 50
- ■ This medication is considered to be a hazardous drug as defined by the National Institute for Occupational Safety and Health (NIOSH). Talk with your veterinarian or pharmacist about the use of personal protective equipment when handling this medicine.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Cyclosporine is a highly lipophilic polypeptide agent originally isolated from the fungus Tolypocladium inflatum. In veterinary ophthalmology, it is the cornerstone therapy for keratoconjunctivitis sicca (KCS), commonly known as dry eye, and chronic superficial keratitis (Pannus) in dogs.
Beyond its tear-stimulating properties, cyclosporine reduces corneal pigmentation and granulation associated with chronic inflammation. Clinical Pearl: Because it is extremely hydrophobic, ophthalmic formulations require specific vehicles (like corn/olive oil in compounded drops, or specific ointment bases) for corneal penetration. It is generally safe for long-term topical use without systemic immunosuppressive side effects.
Mechanism of action
Cyclosporine is a calcineurin inhibitor. It binds to cyclophilin within T-lymphocytes, inhibiting the enzyme calcineurin → prevents dephosphorylation of Nuclear Factor of Activated T-cells (NFAT) → blocks transcription of interleukin-2 (IL-2) and other inflammatory cytokines.
In the eye, this halts local inflammatory mediator production, arresting self-perpetuating lacrimal adenitis. It also acts as a prolactin analog, fitting onto lacrimal prolactin receptors to directly stimulate tear production. Furthermore, it increases conjunctival mucin stores, improving the overall quality of the tear film.
Safety & warnings
Contraindications
- Feline keratoconjunctivitis sicca associated with active herpes virus infection
- Feline eosinophilic keratitis (historically, though newer evidence varies, the monograph notes it is not promising)
Adverse effects
- Mild ocular irritation upon application
- Aggravation of ophthalmic herpes virus infections (especially in cats)
Precautions
Important: Discontinuation of therapy usually results in the return of clinical signs of KCS within a few days.
Use with caution in the face of ulcerative keratitis, although it is generally considered safe when concurrent antibiotic therapy is administered. Compounded formulations should be avoided if an approved commercial product (Optimmune) is available and effective.
Drug interactions
Inhibits cytochrome P450 metabolism of ciclosporin, increasing blood concentrations up to five-fold. Dose reduction (halving dose or doubling interval) is required.
Inhibits cytochrome P450 metabolism of ciclosporin, significantly increasing blood concentrations.
Competitively inhibits enzymes involved in ciclosporin metabolism, increasing serum levels.
Inhibits enzymes involved in ciclosporin metabolism, increasing serum levels.
Increased risk of nephrotoxicity; concomitant use is not recommended.
Increased risk of nephrotoxicity; concomitant use is not recommended.
Increased risk of nephrotoxicity; concomitant use is not recommended.
Increased risk of nephrotoxicity; concomitant use is not recommended.
Increased risk of hyperkalaemia.
Ciclosporin inhibits MDR1 P-glycoprotein, decreasing the efflux of macrocyclic lactones from the blood-brain barrier, potentially resulting in CNS toxicity.
Monitoring
- Schirmer Tear Test (STT) after 1 month of therapy, then periodically
- Fluorescein staining to monitor for corneal ulceration
- Resolution of corneal pigmentation and neovascularization
Pharmacokinetics
Half-life
Absorption
Poor systemic absorption across the GI tract. When delivered topically to the eye, it reaches very low systemic concentrations. Trace levels may be detected in blood but clinical implication is uncertain.
Distribution
Concentrates locally in the cornea, conjunctiva, and lacrimal glands.
Metabolism
Hepatic (Cytochrome P450 3A4) if absorbed systemically.
Elimination
Primarily biliary/fecal if absorbed systemically.
Overdose
Systemic toxicity has not been noted in dogs given this drug chronically via the topical ophthalmic route. Even if 100% of the ophthalmic dose were absorbed, it is well below the systemic therapeutic/toxic dose.
Available products
Formulations
- 0.2% ophthalmic ointment
- 0.05% ophthalmic emulsion
- 1% ophthalmic solution (compounded)
Veterinary
- Cyclosporine Ophthalmic Ointment 0.2% (Optimmune)
Human-labeled
- Cyclosporine 0.05% Ophthalmic Emulsion (Restasis)
Regulatory status
POM-V classification
POM-V classification
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at room temperature away from moisture and heat. Keep the tube tightly closed.
Client information
Managing Your Pet's Dry Eye
- Patience is Key: It can take 3 to 8 weeks of consistent use before you see a dramatic improvement in tear production. Do not stop the medication early!
- Lifelong Therapy: Dry eye (KCS) is usually a lifelong condition. If you stop applying the ointment, the dry eye symptoms will likely return within a few days.
- Application: Apply a small strip (about 1/4 inch) of ointment directly to the eye. If you are also using artificial tears, apply the artificial tears first, wait 5-10 minutes, and then apply the cyclosporine ointment.
- Safety: This medication is very safe for the eyes and does not cause the body-wide side effects that steroids can.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.