Ophthalmic preparations solutions

Ophthalmic preparations (solutions and suspensions) are sterile aqueous preparations with other qualities essential to the safety and comfort of the patient. Ophthalmic ointments must be sterile and free from grittiness. 

Ophthalmic Dosage Forms. Ophthalmic preparations can be solutions, eg, eye drops, eyewashes, ointments, or aqueous suspensions (30). They must be sterile and any suspended dmg particles must be of a very fine particle size. Solutions must be particle free and isotonic with tears. Thus, the osmotic pressure must equal that of normal saline (0.9% sodium chloride) solution. Hypotonic solutions are adjusted to be isotonic by addition of calculated amounts of tonicity adjusters, eg, sodium chloride, boric acid, or sodium nitrate. 

Educating the Patient and Famiiy The patient or a family member will require instruction in die technique of instilling an ophthalmic preparation (see Home Care Checklist Instilling an Ophthalmic Preparation). In addition, die nurse may give the following information to die patient and family member when an eye ointment or solution is prescribed ... 

This preservative is comparatively new to ophthalmic preparations and is a polymeric quaternary ammonium germicide. Its advantage over other quaternary ammonium seems to be its inability to penetrate ocular tissues, especially the cornea. It has been used at concentrations of 0.001-0.01% in contact lens solutions as well as dry eye products. At clinically effective levels of preservative, POLYQUAD is approximately 10 times less toxic than benzalkonium chloride [87,137], Various in vitro tests and in vivo evaluations substantiate the safety of this compound [137,141,142], This preservative has been extremely useful for soft contact lens solutions because it has the least propensity to adsorb onto or absorb into these lenses, and it has a practically nonexistent potential for sensitization. Its ad-sorption/absorption with high water and high ionic lenses can be resolved by carefully balancing formulation components [143],... 

Topically administered ophthalmic preparations can affect visual acuity. Examples are lubricating gels and ointments for dry eye, antimicrobial ointments for ocular infections, and gel-forming solutions for glaucoma. Although acuity is only slightly reduced and is only temporary, this effect can be annoying to patients and may lead to noncompliance. 

Expiration dates of solutions should be respected. Office staff should periodically survey ophthalmic preparations in the office and discard solutions that have reached the expiration date.The use of old solutions can increase liability as well as introduce the risk of potential drug toxicity or iatrogenic infection. Some commonly used ophthalmic solutions, such as proparacaine, may change color, which indicates oxidation (Figure 3-2), whereas others show no visible signs of deterioration. 

Included in the FDA Inactive Ingredients Guide (dental preparations inhalations IM, IV, and SC injections nasal and ophthalmic preparations oral capsules, solutions, suspensions, syrups, and tablets rectal, topical, and transdermal preparations). Included in the Canadian List of Acceptable Non-medicinal Ingredients. Included in nonparenteral and parenteral medicines licensed in the UK. 

The topical use of solutions containing greater than 5% w/v benzethonium chloride can cause irritation although benzethonium chloride is not regarded as a sensitizer. The use of 0.5% w/v benzethonium chloride in cosmetics is associated with few adverse effects. A maximum concentration of 0.02% w/v benzethonium chloride is recommended for use in cosmetics used in the eye area and this is also the maximum concentration generally used in pharmaceutical formulations such as injections and ophthalmic preparations. ... 

In ophthalmic preparations, irritation of the conjunctiva occurs with chlorhexidine solutions of concentration stronger than 0.1% w/v. Accidental eye contact with 4% w/v chlorhexidine gluconate solution may result in corneal damage. ... 

Chlorobutanol is primarily used in ophthalmic or parenteral dosage forms as an antimicrobial preservative at concentrations up to 0.5% w/v see Section 10. It is commonly used as an antibacterial agent for epinephrine solutions, posterior pituitary extract solutions, and ophthalmic preparations intended for the treatment of miosis. It is especially useful as an antibacterial agent in nonaqueous formulations. Chlorobutanol is also used as a preservative in cosmetics [see Section 16) as a plasticizer for cellulose esters and ethers and has been used therapeutically as a mild sedative and local analgesic. 

In ophthalmic preparations, a 0.5-1.0% w/v solution of a highly substituted, high-viscosity grade of methylcellulose has been used as a vehicle for eye drops. However, hypromellose-based formulations are now preferred for ophthalmic preparations. 

Potassium chloride is widely used in a variety of parenteral and nonparenteral pharmaceutical formulations. Its primary use, in parenteral and ophthalmic preparations, is to produce isotonic solutions. 

GRAS listed. Accepted for use as a food additive in Europe. Included in the EDA Inactive Ingredients Guide (injections ophthalmic preparations oral capsules, solutions, and tablets). Included in parenteral (intravenous infusions and injections) and nonparenteral medicines (ear drops eye lotions oral capsules, chewable tablets, effervescent powders, effervescent tablets, granules, and tablets suppositories and suspensions) licensed in the UK. 

Loss of efficacy associated with prolonged or incorrect storage is a potential problem both with commercial ophthalmic preparations and "fortified" solutions prepared in the clinic. The latter must be handled carefully. 

It is noteworthy that, at least presently, sterilization is not required for all drugs. It depends on the type of administration. Hence, it concerns mostly ophthalmic preparations, sterile topical products and injectable solutions, including intramuscular, intravenous and sub-cutaneous ways. 

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