(artificial tears and lubricants)
Brand name
Comfort Tears, Lacril, Hypotears, Liquifilm Tears, Lacri-Lube, as well as several other brand names.
Availability
- Multiple OTC drop or ointment preparations with or without preservatives.
*Note: preservative-free agents are recommended.
Pharmacology
Artificial tears are an eye solution, used to moisten the eyes as an eye rinse and to prevent dry eyes. Ocular lubricants are used as a protective coating to protect eye(s) from injury.
Natural physiology of tear film consists of three layers that protect the eye and keeps it healthy and free from debris. The outer lipid layer is oily and keeps the tears from evaporating or spilling out of the eye. The middle, aqueous layer nourishes the cornea and conjunctiva and reduces the chance of infection. The last layer, or mucin helps to spread the aqueous layer, ensuring that the eye remains moist.
Artificial tears are preparations that can contain polymers (class of naturally occurring or synthetic compounds) such as: carboxymethyl cellulose, hydroxypropyl methylcellulose (a.k.a HPMC or hypromellose), and hydroxypropyl cellulose preservatives, as well as water and salts, but lack the proteins that are found in natural tears. When having to use them frequently for your pet rat it is recommended to choose a brand without preservatives, or one containing non-irritating preservatives.
Artificial tears are not known to be absorbed into the system, nor cross the placenta, nor enter into breast milk.
Indications
They can be used to reduce irritation and dryness of keratoconjunctivitis, or dry eyes.
Artificial tear preparations are used to maintain eye moisture, as well as to bathe or rinse debris from the eye(s). Lubricants/ointments that are petroleum based are useful in protecting the eyes during anesthetic procedures when tear production is reduced. The eyes, in rats, tend to remain open and the blink reflex may not be present which can lead to corneal abrasion/ulceration and dryness. In addition, lubricants may also be used for protecting the eye(s) when doing other procedures in and around the area of the eye(s).
Drug Interactions or Contraindications
- Artificial tears have no reported interactions.
Adverse Reactions
Possible adverse effects of those artificial tears containing preservatives may include:
- eye irritation and pain
- redness
- changes in vision
- stickiness of eyelashes
Discontinue use if adverse effects #1 and #2 develop and call the veterinarian. Effects #4 and #5 are expected with lubricants due to the thickness of the products.
Dosage Recommendations
Wash hands before and after applying to rat’s eye(s). Very gently pull down the lower eyelid with your index finger to form a pouch. Squeeze one to two drops or ointment into the pouch. Close the eye gently for a few moments to allow the drops to be in contact with the eye. Eye drops may be used several times a day. Ointments are often only needed from one to three times daily, or as directed, since their effect tends to last longer than drops.
The duration of treatment will depend upon the reason for the treatment and the rat’s response to the treatment.
Considerations
- Pet owners should be sure to wash hands before and after applying drops or lubricant to a rat’s eye(s). Wipe excessive lacrimation (porphyrin around the eyes in rats) or debris from eye(s) before application. Do not touch solution tip or tube opening to any surface, including eyes or hands. The solution tip/ tube opening is sterile, and if contaminated it could cause additional infection in the eye.
- Do not use any bottle/tube where the lubricant/ointment is discolored, or the solution has particles in it. Check expiration date.
- Discontinue use, and contact veterinarian, if the following occurs: keratitis, redness, increased lacrimation, swelling of eye, or if rat starts to scratch eye in attempt to relieve itching.
- In most cases unopened ophthalmic lubricant/ointment may be stored for up to a year at room temperature away from moisture and heat, or until expiration date.
- It is recommended that opened bottles/tubes be discarded after 30 days. Check directions on solution bottle.
