Administration routes ointment

Nitroglycerin, the prototype of the nitrates is characterized by a rapid onset and short duration of action. It is usually administered sublingually (via the oro-mucosal route), which allows a rapid and efficient absorption and avoids the strong first pass effect after oral administration. Nitroglycerin is available as tablets, capsules (for sublingual administration) but also as transdermal preparations, sprays, and ointments. 

Polymyxin B and colistin (polymyxin E) (Fig. 3.9) are the least toxic of the five polymyxin antibiotics designated alphabetically A-E. Both polymyxin B and colistin are complex polypeptide compounds with specialized activity against gram-negative organisms but they are both nephrotoxic. Topical application and oral administration are more commonly used routes. Polymyxin B is used widely in ointments for topical applications and may be effective in case of mastitis, but it seldom is administered parenterally because of the possibility of renal toxicity. 

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. 

Ethoxysilatrane proved to be effective in treating wounds also via other routes of administration. Thus, in the second series of tests involving 40 rabbits with skin-muscle wounds of 300 mm2 size 1-ethoxysilatrane was administered both subcutaneously and per os at 50 mg/kg doses and as 5% ointment in a 1 1 vaseline-lanolin base. 

Unlike oral drug therapy in which the dosage imit is usually a tablet or capsule that is swallowed, ocular pharmacotherapy requires a measure of manual dexterity if topical solutions or ointments are to be instilled successfully. When patients cannot successfully instill their ocular medications independently, alternative approaches may need to be considered. Solutions include consideration of altered routes of administration of similar drugs and aid in the administration of the drug by family members or attendants. 

Transdermal administration can avoid first-pass metabolism as well as provide a large surface area for continuous-controlled administration of drugs with short biological half-lives and narrow therapeutical indices. The route has been used for nitroglycerin ointments, and transdermal therapeutical systems (patches) have been developed for scopolamine, nitroglycerin, clonidine, estradiol, and nicotine. 

RNase (RNAse ribonuclease) An enzyme that cleaves RNA. routes of administration of drugs There are many different routes but common ones include intravascular injection or infusion (into the blood vessels, e.g. by drip, mainly intravenous (into veins) but sometimes intra-arterial (into arteries) intramuscular (injection into muscles) subcutaneous (injection beneath the dermis of the skin) intradermal (injection into the skin) transdermal (across the skin. e.g. from skin patches) topical (application to the skin or mucous membranes) per rectum (by an ointment or suppository into the rectum) intravaginally (by an ointment or pessary into the vagina) intrathecal (by injection into the subarachnoid space of the spinal cord) intranasally (often as a spray) orally (by mouth) inhalation. rRNA ribosomal RNA. 

The formulation chosen for particular drugs is not random, but the degree to which it is critical varies from drug to drug. For example, hydrocortisone is available for at least seven routes of administration, as tablets, several creams and ointments, intraocular solutions, suppositories, intrarectal foams, injections and eardrops. Even newer drugs, with fewer indications than hydrocortisone, seek greater market acceptability by providing a variety of alternative formulations (e.g. sumatriptan is available as an injection, intranasal spray, suppository and tablets). 

There are two main ways by which substances may be administered to humans the enteral and the parenteral routes. For enteral administration the substance is placed directly into the gastrointestinal tract by permitting a tablet to dissolve when it is placed under the tongue (sub-lingual administration), or by swallowing a tablet, capsule or a solution (oral) or by rectal administration as a suppository. In parenteral administration the substance in solution may be injected subcutaneously, intramuscularly or intravascularly, inhaled as an aerosol, applied topically to the skin as a cream or ointment, or, rarely, in the form of a pessary. 

Percutaneous absorption may be increased substantially in newborns because of an underdeveloped epidermal barrier (stratum comeum) and increased skin hydration. The increased permeability can produce toxic effects after the topical use of hexachlorophene soaps and powders, salicyhc acid ointment, and rubbing alcohol. Interestingly, a study has shown that a therapeutic serum concentration of theophylline can be achieved to control apnea in premature infants of less than 30 weeks gestation after a topical apphcation of gel containing a standard dose of theophylline. " The use of this route of administration may minimize the unpredictability of oral and intramuscular absorption and complications of intravenous drug administration for certain drugs. 

Semisolid Dosage Forms [SUPAC-SS] — Semisolid dosage forms include nonsterile and semisolid preparations, for example, creams, gels, and ointments, intended for all topical routes of administration. 

Drugs which are suitable for administration via the transdermal route include those of low molecular weight (400-800). Other factors, such as increasing the temperature and pH, decreasing skin thickness and increasing hydration by using occlusive bases such as ointments and the use of patches, can facilitate penetration of drugs into the skin. 

According to national legislation the label mentions the dosage form (eye cream or eye ointment), the route of administration (ocular use), the intended use, the storage conditions, the expiry date and, for multidose containers, the beyond-use date after which the opened preparation must not be used. This period should not exceed 4 weeks. If necessary the label also bears warnings and mentions that the contents should be brought to room temperature before administration if the tube is stored in the refrigerator. 

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