Administration routes subcutaneous

Effects in Animals. The LD ia rats for all light chlorophenols, irrespective of the administration route, ties between 130 and 4000 mg/kg body weight. The toxicity of these compounds ia order of increasing strength is tetrachlorophenols > monochloropheno1 s > dichlorophenols > trichlorophenols when the chlorophenol is administered either orally or by subcutaneous iajection. 

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. 

Parenteral administration of drugs by intravenous (IV), intramuscular (IM), or subcutaneous (SC) routes is now an established and essential part of medical practice. Advantages for parenterally administered drugs include the following rapid onset, predictable effect, predictable and nearly complete bioavailability, and avoidance of the gastrointestinal (GI) tract and, hence, the problems of variable absorption, drug inactivation, and GI distress. In addition, the parenteral route provides reliable drug administration in very ill or comatose patients. 

Yoshimura et al. [132] studied the pharmacokinetics of primaquine in calves of 180—300 kg live weight. The drug was injected at 0.29 mg/kg (0.51 mg/kg as primaquine diphosphate) intravenously or subcutaneously and the plasma concentrations of primaquine and its metabolite carboxyprimaquine were determined by high performance liquid chromatography. The extrapolated concentration of primaquine at zero time after the intravenous administration was 0.5 0.48 pg/mL which decreased with an elimination half-life of 0.16 0.07 h. Primaquine was rapidly converted to carboxyprimaquine after either route of administration. The peak concentration of carboxyprimaquine was 0.5 0.08 pg/mL at 1.67 0.15 h after intravenous administration. The corresponding value was 0.47 0.07 pg/mL at 5.05 1.2 h after subcutaneous administration. The elimination half-lives of carboxyprimaquine after intravenous and subcutaneous administration were 15.06 0.99 h and 12.26 3.6 h, respectively. 

UFH must be given parenterally, preferably by the IV or subcutaneous (SC) route. Intramuscular administration is discouraged because absorption is erratic and it may cause large hematomas. 

The route of administration of an NCE is typically the intended clinical route of administration. However, an alternative route may be used if this leads to an increase in systemic exposure of parent drug or major metabolites or if this alternative route satisfies another important objective of the study. For example, it is common to increase the exposure following inhalation administration by associating a subcutaneous administration of the NCE. 

Route of administration alters the effectiveness of cannabinoids. Orally administered THC has a slower and more erratic absorption. THC was found to be 45 times more effective for analgesia after intravenous than after subcutaneous administration (Martin 1985). The pharmacokinetics of different chemical constituents of cannabis vary (Consroe et al. 1991). The elimination half-life of cannabidiol is estimated to be about 2-5 days, with no differences between genders. Comparably, the elimination half-life of Al-THC is approximately 4 days, and may be prolonged in chronic users (Johansson et al. 1988, 1989). 

Route of administration For subcutaneous administration only do not administer IM or IV. 

Bethanechol is used to treat postsurgical bladder dysfunction associated with the retention of urine. It is most commonly given orally for this purpose, although the subcutaneous route is also used. Effects are more rapid and intense after subcutaneous administration, but the duration of action is shorter. 

Route of administration Aranesp is intended for intravenous or subcutaneous administration as a single weekly injection. 

Route of administration Roferon-A can be administered intramuscularly or subcutaneously. The route of administration for the prefilled syringe is subcutaneous only. 

Route of administration PEG-Intron is intended for subcutaneous administration. A patient can self-inject PEG-Intron if the physician determines that it is appropriate, if the patient agrees, and if training in proper injection technique has been given to the patient. 

Route of administration Antagon is intended for subcutaneous administration. 

LAE-32, N-ethyllysergamide. Different people have observed and reported different effects, with different routes of administration. Subcutaneous administrations of from 500 to 750 micrograms have been said to produce a state of apathy and sedation. Clinical studies with dosages of 500 micrograms i.m. were felt to be less effective than the control use of 100 micrograms of LSD. And yet, oral doses of twice this amount, 1.6 milligrams, have been said to produce a short-lived LSD-like effect with none of these negatives. 

Following either oral or parenteral administration, levamisole is rapidly absorbed, but the parenteral route produces higher blood levels (6). When given intramuscularly, peak plasma levels are almost twice those attained by oral administration of the same dose. After subcutaneous administration, peak plasma levels of levamisole occur within 30 min, with 90% of the total dose being excreted in 24 h, mainly in the urine. 

The pharmacokinetics of ivermectin differ with the animal species, formulation, and the route of administration (50). When goats were given a subcutaneous administration of 0.2 mg ivermectin /kg bw, the mean concentrations of ivermectin in plasma and milk increased initially to reach at 2.8 day the maximum levels of 6.12 and 7.26 ppb, respectively (51). The drug could be detected in milk for 25 days postdosing, the total drug amount recovered over this period being estimated at 0.6% of the administered dose. This percentage is low compared with the 4% level determined in sheep (52) and 5.6% in cows (53). 

Mora and coworkers201 studied the in vivo interaction, in mice, of toxic levels of cationic macromolecules with the carboxyl and sulfate derivatives of polyglucose. Toxic levels of polymyxin, protamine, streptomycin, and neomycin could be counteracted, if the synthetic macroanions were injected five to ten minutes after administration of the proteins. Subcutaneous administration of the anionic polyglucoses prior to intra-peri toneal injection of toxic levels of basic proteins afforded protection to the mice, and also demonstrated that the animals could survive, even when the two injections were by different routes. 

Subcutaneous. Injecting medications directly beneath the skin is used when a local response is desired, such as in certain situations requiring local anesthesia. Also, a slower, more prolonged release of the medication into the systemic circulation can be achieved in situations where this is the desired effect. A primary example is insulin injection in a patient with diabetes mellitus. Subcutaneous administration provides a relatively easy route of parenteral injection that can be performed by patients themselves, providing they are properly trained. 

Some limitations are that the amount of drug that can be injected in this fashion is fairly small and that the injected drug must not irritate or inflame the subcutaneous tissues. The subcutaneous route can also be used when certain types of drug preparations are implanted surgically beneath the skin, so that the drug is slowly dispersed from the implanted preparation and then absorbed into the bloodstream for prolonged periods of time.62,86 A common example of this form of subcutaneous administration is the use of implanted hormonal contraceptive products (e.g., Norplant).9,53 The use of these implantable contraceptives is discussed in more detail in Chapter 30. 

The LMWHs appear to be as effective as unfractionated (mixed) heparins, but they offer certain advantages. For example, LMWHs can be administered by subcutaneous injection into fat tissues, thereby decreasing the need for repeated intravenous administration. Subcutaneous administration offers an easier and more convenient route, especially for people who are being treated at home or as outpatients.98 118 Dosing schedules of LMWHs are typically easier (once per day), compared to 2 or more daily injections of unfractioned heparin.132 The anticoagulant effects of LMWHs are also more predictable, and... 

Due to their high molecular mass (and other reasons), the vast majority of mAbs that have been approved or are currently in clinical development are administered by intravenous (IV) infusion. This route allows the total dose to be available in the circulation, as F (the systemically available fraction of the dose) is, by definition, 1. In consequence, maximum concentrations in serum are rapidly observed, and are higher compared to those achieved by other routes. Therefore, adverse reactions after IV administration occur more often but are generally reversible. In addition, IV infusions represent the most inconvenient (they often require hospitalization) as well as time- and cost-consuming means of administration. Consequently, ex-travascular routes have been chosen as alternatives, including subcutaneous administration (SC e. g., adalimumab, efalizumab) and intramuscular administration (IM e.g., palivizumab) (Table 3.4). 

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