Administration routes intramuscular injection

The advantages of administration by intramuscular injection are that the muscle can act as a depot, and the rate of disappearance of drug from the site of injection can be calculated. Inhalational, intranasal, and intratracheal administration are normally reserved for vapors and aerosols including anesthetics. Absorption is facilitated by small-sized particles, high lipid solubility, sufficient pulmonary blood flow, and a large absorptive surface area, as it is present in healthy lungs. Administration by these routes can be very rapid when several of the factors favoring increased absorption are combined. 

The route of antigen administration depends on the nature of the antigen itself, the animal species, the use of an adjuvant, and the immunological response. When producing antisera from rabbits, subcutaneous and intradermal administration are the most popular routes. Intramuscular injections can be used in the presence of Freund adjuvants because this route provides rapid access to the lymphatic system. The intravenous route is used with particulate antigens because injection can produce a response, which, although rapid, is not sustained. 

Opioids maybe administered in a variety of routes including oral (tablet and liquid), sublingual, rectal, transdermal, transmucosal, intravenous, subcutaneous, and intraspinal. While the oral and transdermal routes are most common, the method of administration is based on patient needs (severity of pain) and characteristics (swallowing difficulty and preference). Oral opioids have an onset of effect of 45 minutes, so intravenous or subcutaneous administration maybe preferred if more rapid relief is desired. Intramuscular injections are not recommended because of pain at the injection site and wide fluctuations in drug absorption and peak plasma concentrations achieved. More invasive routes of administration such as PCA and intraspinal (epidural and intrathecal) are primarily used postoperatively, but may also be used in refractory chronic pain situations. PCA delivers a self-administered dose via an infusion pump with a preprogrammed dose, minimum dosing interval, and maximum hourly dose. Morphine, fentanyl, and hydromorphone are commonly administered via PCA pumps by the intravenous route, but less frequently by the subcutaneous or epidural route. 

Liposomes tend to remain at the injection site when they are administered intramuscularly or subcutaneously. Therefore, these administration routes are useful for slow and sustained release of drugs at the injection site. 

Chickens rapidly excrete arsenicals only 2% of dietary sodium arsenite remained after 60 h (NAS 1977), and arsanilic acid was excreted largely unchanged (Woolson 1975). Excretion of arsanilic acid by chickens was affected by uptake route excretion was more rapid if administration was by intramuscular injection than if it was oral (NRCC 1978). Studies with inorganic As+5 and chickens indicated that (Fullmer and Wasserman 1986) ... 

A third consideration is that certain routes of administration may favor immu-nogenicity of recombinant proteins. In early trials, rDNA proteins introduced by subcutaneous or intramuscular injections (procedures known to improve the immu-nogenicity of proteins) resulted in a higher frequency of antibody responses than in the intravenous route. 

It seems likely that most of the losses following topical aldrin application are due to poor absorption rather than to elimination. The intramuscular route is being used as a means to obtain long-term, low level exposures. Since these procedures permit in situ administration of test compounds, an operation difficult or impossible with the more common immersion strategy for dosing, intramuscular injections will receive increased attention and evaluation. 

Alternative options are increasingly favoured in the form of oral iron polymaltose complexes. These are more expensive but attractive in that complications are less frequently encountered and the lethal toxicity that follows release of large amounts or ionic iron into the circulation does not occur. Carbonyl iron is not often used but available in some countries. In contrast combinations with vitamins and cobalt, still popular in certain areas, have no documented advantage and add quite unnecessary cost. Other routes are intramuscular injections and, except where oral administration is precluded, have disadvantages in that mobilization is unpredictable. Conversely, it is feasible to replace iron as a single total dose infusion but such procedures need to be given under supervised conditions. It is reiterated that the rate of rise in haemoglobin that follows adequate oral replacement is comparable to that achieved par-enterally. 

The xanthines are readily absorbed by the oral and rectal routes. Although these agents can be administered by injection (aminophylline is a soluble salt of theophylline), intravascular administration is indicated only in status asthmaticus and apnea in premature infants. Intramuscular injection generally produces considerable pain at the injection site. 

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. 

Calcitonin (Miacalcin, Miacalcin Nasal Spray) is a synthetic 32-amino acid polypeptide that is identical to salmon calcitonin. Salmon calcitonin is more potent than human calcitonin because of its higher affinity for the human calcitonin receptor and its slower metabolic clearance. Administration is by subcutaneous or intramuscular injection or by nasal spray. The absorption of the nasal form is slower than that of the parenteral routes. 

Most BZs are completely absorbed from the gastrointestinal (GI) tract. The one exception is clorazepate, a pro-drug that undergoes acid hydrolysis in the stomach and is decarboxylated to form N-desmethyl-diazepam, which is then completely absorbed into the bloodstream (Bellantuono et ak, 1980 Hobbs et ak, 1996 Chouinard et ak, 1999). In contrast, most BZs, with the exception of lorazepam and midazolam, are not consistently absorbed from intramuscular injection (Chouinard et ak, 1999). Lorazepam is available as a sublingual form that reaches clinical effect at the same rate as an oral dose. In general, intravenous administration is used only for anesthesia or for the acute management of seizures. When BZs are given via this route, the onset of action is almost immediate (Chouinard et ak, 1999). 

Parenteral administration This route is applicable for drugs which are inactivated by gastrointestinal tract or absorption is poor when given orally or there is a urgency for fast response in small dose. Intramuscular, intravenous, or subcutaneous routes are commonly used. The intravenous injection (in aqueous solution) is introduced directly into the vein by which a rapid response is produced. The subcutaneous injection are given through the layer of skin, while intramuscular injection, introduced through the skin layer deep into the muscle. The nature of intramuscular injection may be in aqueous or oily solution/suspension form. The aqueous solution will be rapidly absorbed as compared to oily solution or suspension. So, the rate of absorption is dependent on the nature of the preparation. 

Route of administration Glucagon for injection (rDNA origin) may be administered intravenously, intramuscularly, or subcutaneously. 

Route of administration Lupron Injection is intended for subcutaneous injection. Lupron Depot is intended for intramuscular injection. 

Route of administration Adagen should only be given by intramuscular injection and should not be diluted or mixed with other drugs prior to use. 

Route of administration Reconstituted Synagis is to be administered by intramuscular injection only. 

Absorption of phenytoin is highly dependent on the formulation of the dosage form. Particle size and pharmaceutical additives affect both the rate and the extent of absorption. Absorption of phenytoin sodium from the gastrointestinal tract is nearly complete in most patients, although the time to peak may range from 3 to 12 hours. Absorption after intramuscular injection is unpredictable, and some drug precipitation in the muscle occurs this route of administration is not recommended for phenytoin. In contrast, fosphenytoin, a more soluble phosphate prodrug of phenytoin, is well absorbed after intramuscular administration. 

Iron dextran is a stable complex of ferric oxyhydroxide and dextran polymers containing 50 mg of elemental iron per milliliter of solution. It can be given by deep intramuscular injection or by intravenous infusion, although the intravenous route is used most commonly. Intravenous administration eliminates the local pain and tissue staining that often occur... 

Results of pharmacokinetic studies of streptomycin are in most cases also applicable to dihydrostreptomycin and vice versa. In animals, the absorption of both streptomycin and dihydrostreptomycin is poor via the oral route but rapid after intramuscular administration. In cattle, peak serum levels were obtained 1 h after intramuscular injection of either streptomycin or dihydrostreptomycin (18), whereas serum concentrations produced in sheep and horses paralleled those obtained in cattle (19). As a result, most of an oral dose is recovered in the feces whereas most of a parenteral dose is recovered in the urine. However, if kidney function is severely impaired, little of an intramuscularly administered dose is excreted in the urine. 

Although it is not a major elimination route following intravenous or intramuscular injection of penicillin G to dairy cattle, milk constitutes a very important route of elimination following intramammary injection since most of the dose enters milk (58, 59). The persistence of residues in milk does depend on the formulation and route of administration, but, in a wide variety of trials, residues were not found to persist beyond 5 days after the end of treatment (59, 60). Transfer of penicillin G from treated to untreated quarters has also been observed... 

Studies of the carcinogenicity of chloroprene by the oral route or inhalation, intratracheal administration, subcutaneous or intramuscular injection or skin application were reviewed by lARC (1979) and found inadequate for evaluation. These studies are not considered further. 

Intramuscular. The large quantity of skeletal muscle in the body allows this route to be an easily accessible site for parenteral administration. Intramuscular injections can be used to treat a problem located directly in the injected muscle. For example, botu-linum toxin and other substances can be injected directly into hyperexcitable muscles to control certain types of muscle spasms or spasticity (see Chapter 13).7,78 Alternatively, intramuscular injection can be used as a method for a relatively steady, prolonged release of the drug into the systemic circulation to control conditions such as psychosis,2 or to administer certain vaccines. 

Several types of CDD systems have been designed based on various mechanisms of drug release (Table I). These mechanisms are dependent on the required site of drug delivery, the physicochemical properties of the drug and also of the delivery vehicle (13), Modes of administration can be oral, sublingual, transdermal, rectal, intrauterine, ocular, or parenteral (intramuscular, peritoneal, and subcutaneous routes of injection). 

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