Cyclosporine (Systemic)

What is this medication for?

• Atopic dermatitis (well-established, similar efficacy to prednisolone), perianal fistulas, IMHA (refractory), IBD
• Allergic dermatitis (Atopica for cats), eosinophilic granuloma complex, IBD, feline asthma, mouth sores

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

• Sandimmune and Atopica/Neoral are NOT bioequivalent — dosing tables differ; never assume interchangeability between formulations.
• Response for atopic dermatitis may take 2–4 weeks — bridge with other antipruritics (steroids, oclacitinib) during the induction period.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Vomiting, loss of appetite, diarrhea (Most common, especially early in therapy)
• Gingival hyperplasia, hypertrichosis, papillomatosis (With chronic use)
• Reactivation of latent viral infection (esp. FHV-1) (Documented)

Worth a phone call to your veterinarian

• Nephro/liver damage (Only at very high blood levels (>3000 ng/mL))

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Trouble breathing, collapse, seizures, severe vomiting or diarrhea, facial swelling, or pale gums

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Hypersensitivity; history of malignant neoplasia (dog label); do not use in FeLV/FIV-positive cats
• has or has had: Hepatic/renal disease; check FeLV/FIV status before starting in cats; naive (seronegative) cats at ↑ risk of clinical toxoplasmosis if exposed while on the drug

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Azole antifungals (ketoconazole, itraconazole, fluconazole)
  • Macrolides, cimetidine, metoclopramide, grapefruit juice
  • Rifampin, phenobarbital, phenytoin, griseofulvin
  • NSAIDs, aminoglycosides, other kidney damage drugs
  • Live vaccines

Storage and handling

Room temperature. Unpleasant taste — compounding into gelatin capsules can help palatability.

Good to know

• Sandimmune and Atopica/Neoral are NOT bioequivalent — dosing tables differ; never assume interchangeability between formulations.
• Vomiting is common when starting therapy — a gradual dose-escalation protocol with early metoclopramide can improve tolerance.
• Response for atopic dermatitis may take 2–4 weeks — bridge with other antipruritics (steroids, oclacitinib) during the induction period.
• Ketoconazole co-administration is a well-established, deliberate cost-reduction strategy — but requires blood-level monitoring awareness.