Topical administration suspension

An 11-year-old boy with iridocyclitis developed Cushing s syndrome, a posterior subcapsular cataract, and increased intraocular pressure in both eyes after the topical administration of prednisolone acetate 1% eye-drops bilaterally for 6 months. The Cushing s syndrome was aggravated when periocular methylpredni-solone acetate was started while bilateral posterior subtenon injections of 80 mg of suspension were continued every 6 weeks for 6 months. He had not used systemic glucocorticoids before. 

Itraconazole Topical 1% suspension 1 drop qlh Oral 200 mg PO qd-bid Topical not effective for severe infections, penetrates cornea poorly not commercially available must be compounded Penetrates all eye tissues poorly with oral administration Side effects include hepatotoxicity, gastrointestinal problems, hypokalemia, elevated Uver enzymes, rash, vasculitis, headache, fever, HTN, hypertriglyceridemia Many drug interactions exist including CYP3A4 substrates. Coadministration of itraconazole is contraindicated with multiple antiretrovirals (refer to Table 11-12) Pregnancy category C lactation safety unknown... 

This chitosan amphiphile nanomedicine also promotes the transport of drugs across the cornea on topical administration, producing similar aqueous humour levels at the 1 h time point as when the drug is applied as a suspension at ten-fold the nanomedicine dose. ... 

How to administer topical antifungal agents, including cleaning the oral cavity prior to administration, administering after meals, how to dissolve troches, and how to swish suspensions... 

Glucocorticoids are available in a wide range of preparations, so that they can be administered parenterally, orally, topically, or by inhalation. Obviously the oral route is preferred for prolonged therapy. However, parenteral administration is required in certain circumstances. Intramuscular injection of a water-soluble ester (phosphate or succinate) formed by esterification of the C21 steroid alcohol produces peak plasma steroid levels within 1 hour. Such preparations are useful in emergencies. By contrast, acetate and tertiary butylacetate esters must be injected locally as suspensions and are slowly absorbed from the injection site, which prolongs their effectiveness to approximately 8 hours. 

Nystatin is available as an ointment for topical applications and as a suspension or tablet for oral administration. It is approved for oral administration at 100,000 lU/day for 7 days in chickens and turkeys by the Food and Drug Administration (FDA), but it is also used in cattle for treatment of genital mycoses. Nystatin is remarkably low in toxicity when given orally, but it is much more toxic after parenteral administration. 

For liquid (e.g., solution, suspension, elixir) and semisolid (e.g., creams, ointments) dosage forms, a change to or in polymeric materials (e.g., plastic, rubber) of primary packaging components, when the composition of the component as changed has never been used in a CDER-approved product of the same dosage form and same route of administration. For example, a polymeric material that has been used in a CDER-approved topical ointment would not be considered CDER-ap-proved for use with an ophthalmic oinhnent. 

Historically, the administration of crystalline APIs has mainly found use in parenteral applications associated with intramuscular and subcutaneous injections as well as topical applications of suspensions containing micronized APIs. Commercially marketed pharmaceuticals categorized as suspensions for parenteral administration are illustrated in Table 17.3. Many of these products utilize drug substance size reduction in order to promote dissolution following administration. The degree... 

Miconazole comes in topical (1% ophthalmic suspension), subconjunctival depot (10 mg/0.5 ml), and oral (200-400 mg/day) formulations but is not commercially available now in any of these formulations. Miconazole is relatively broad spectrum and active against most yeast but has variable coverage of Aspergillus and Fusarium. Miconazole is generally well tolerated with topical and subconjunctival administration, but cases of corneal toxicity have been reported. 

Enemas These are available as solutions (aqueous or oily) as well as suspensions for rectal administration of drugs for cleaning, diagnostic, or therapeutic effect. Lotions These are available as solutions and suspensions to be applied topically without friction. They may either contain humectant, so that moisture is retained on the skin after application, or alcohol, which evaporates quickly imparting a cooling sensation to the skin. 

Pharmaceutical nanosuspensions are usually very finely dispersed solid drug particles in an aqueous vehicle for either oral and topical use or for parenteral and pulmonary administration. The key difference from conventional suspensions is that the particle size distribution of the solid particles in nanosuspensions is usually less than 1 pm, with an average particle size range between 200 and 600 nm. 

Many oral solutions are intended for pediatric administration, of which oral solution formulations are a subset of a larger choice of formulation type such as suspension, syrup, powder or microcapsules for constitution to a suspension, powder for reconstitution to a solution or suspension, solid particles (powder, coated particles, extended release, enteric-coated granules, beads) in packets or capsules to be sprinkled on food, oral powders, and chewable tablets. The broader topic of pediatric formulation development is beyond the scope of this chapter, but this chapter will cover selected oral solutions for pediatric administration. 

Most ocular diseases like dryness, conjunctiva, and eye flu are treated by topical drug application in the form of solutions, suspensions, and ointment. In the earlier period, drug delivery to the eye has been limited to topical application, redistribution into the eye following systemic administration, or direct intraocular/periocular injections. However, one of the major barriers of ocular medication is to obtain and maintain a therapeutic level at the site of action for a prolonged period of time. 

Other routes of administration arc theoretically possible such as rectal route (rectal capsules and rectal suppositories) for drugs having systemic effects such a.s sedatives, tranquilizers, and analgesics topical route (patchs) for drug absorption (hormones or nicotine) into the systemic circulation parenteral route (administration of parenteral suspensions or implantation of compressed pellets). 

Routes other than oral are possible for administration of the dry adsorbed emulsions such as the rectal route (soft cap.sules, suppositories), the parenteral route (parenteral suspensions, compressed pellets for implamaiioti). and the topical mute (patchs). 

The topical route is almost exclusively intended for delivery of drugs to treat ophthalmic anterior segment diseases. For topical ocular administration, liquid formulations under solutions or suspensions, ointments and soluble gels are the most commonly applied because they are easy to use and do not interfere with vision. Nevertheless, these formulations are often quite ineffective due to dilution in the tear... 

---