Subcutaneous injection sites

Subcutaneous irritation is evaluated as follows Rabbits are euthanized by a lethal dose of barbiturate approximately 24 and 72 h after dosing. The subcutaneous injection sites are exposed by dissection, and the reaction is scored for irritation on a scale of 0 to 5 as follows (Shintani et al., 1967 USP, 1995a) ... 

Cyanocoba/am/n- Cyanocobalamin is rapidly absorbed from IM and subcutaneous injection sites the plasma level peaks within 1 hour. Once absorbed, it is bound to plasma proteins, stored mainly in the liver and is slowly released when needed to carry out normal cellular metabolic functions. Within 48 hours after injection of 100 to 1,000 meg of vitamin B-12, 50% to 98%... 

Pharmacokinetics Insulin glargine is characterized by slow absorption from the subcutaneous injection site and a fiat plasma insulin profile. Absorption patterns are similar after subcutaneous injection into the arm, abdomen, or thigh. A study in patients with type 1 diabetes found that the median time between injection and the end... 

Gonadorelin can cause headache, light-headedness, nausea, and flushing. Local swelling often occurs at subcutaneous injection sites. Generalized hypersensitivity dermatitis has occurred after long-term subcutaneous administration. Rare acute hypersensitivity reactions include bronchospasm and anaphylaxis. Sudden pituitary apoplexy and blindness have... 

Owens DR, Coates PA, Luzio SD, Tinbergen JP, Kurzhals R. Pharmacokinetics of 125I-labeled insulin glargine (HOE 901) in healthy men comparison with NPH insulin and the influence of different subcutaneous injection sites. Diabetes Care 2000 23(6) 813-9. 

Most compelling reason to be concerned about carcinogenic potential of T-20 is that the subcutaneous administration of T-20 causes chronic inflammation. This adverse effect in humans can be monitored in humans Rats have limited body surface area for subcutaneous injections sites and the procedure harms the rats... 

Kanazawa K, Birbeck MS, Carter RE, et al. 1969. Migration of asbestos fibers from subcutaneous injection sites in mice. Br J Cancer 24 96-106. 

GM-CSF often causes erythema and itching at subcutaneous injection sites, with a particularly high incidence of relapsing macular pruritic infiltrates at sites of injection in patients with inflammatory breast cancer (SEDA-20, 339). Based on a retrospective review, molgramostim-induced rash was the most common treatment-limiting adverse event in bone marrow transplant patients, but further administration of sargramostim may be well tolerated (1). 

In a study involving 11 insulin-dependent diabetic subjects, leg exercise accelerated insulin absorption from a subcutaneous injection site in the leg, whereas it had no effect on insulin absorption from the arm and reduced it from the abdomen (Koivisto and Felig, 1978). Most exercise involved many muscle groups, and increased absorption was still likely. Patients who developed hypoglycaemia were advised to take extra carbohydrate before exercise rather than decrease the insulin dose (Zinman et al., 1978). Studies in five subjects suggested that absorption was increased by exercise (Koivisto, 1980a). 

Studies in eight insulin-dependent diabetic men indicated that a sauna accelerated insulin absorption from the subcutaneous injection site and that, 2 h after the sauna, mean blood glucose concentration was significantly lower than on the control day (Dandona etal., 1978 Cuppers et al., 1980 Koivisto, 1980b). Hypoglycaemia and seizures were observed in one patient after the use of a sunbed (Husband and Gill, 1984). 

Possible advantages of intraperitoneal versus subcutaneous insulin include the avoidance of erratic absorption (both rate and extent of absorption), convenience, avoidance of subcutaneous injection site-related complications, and prevention of peripheral hyperinsulinemia. Insulin appears to be cleared into the systemic compartment by an active transport process, or via the peritoneal lymphatics. A number of studies have demonstrated the bioavailability of intraperitoneal insufin to be about 25% to 30%, although none clearly compares the clinical effectiveness of intraperitoneal versus subcutaneous insufin in diabetes control. Insufin requirements for PD patients may be greater than in hemodialysis patients because of the continued absorption of dextrose from the peritoneal cavity. Furthermore, because of adsorption of insufin to the polyvinyl chloride bag and administration set, the intraperitoneal dose of insufin often needs to be two to three times the subcutaneous maintenance dose. 

Nanoparticles with insulin adsorbed onto the surface (Douglas et al, 1987) or liposomes loaded with insulin have also been utilized for sustained release after subcutaneous, intramuscular, or intraperitoneal administration (Patel and Ryman, 1976 Couvreur et al, 1980 Stevenson et al., 1982 Weiner eta/., 1985 Spangler, 1990). However, most injected liposomes and their content of insulin apparently remained at the subcutaneous injection site(Spangler, 1990). 

Linde, B., 1986, Dissociation of insulin absorption and blood flow during massage of a subcutaneous injection site. Diabetes Care 9 570-574. 

The liposome gel delivery system and liposome surface modified with fibronectin offer several advantages over other liposome formulations or gel formulations constructed only with free drug [96], Two peptide hormones, insulin and growth hormone encapsulated in vesicles sequestered within the matrix, are slowly released into the circulation from either an intramuscular or subcutaneous injection site. A maximum 3-5-d release for insulin or a 14-d growth hormone release was observed. 

IFN s pharmacokinetic characteristics limit its therapeutic efficacy. IFN is rapidly absorbed from the subcutaneous injection site, and peak semm concentrations occur 3 to 8 hours after dosing. IFN is rapidly cleared by renal filtration, reabsorption and catabolism in the kidney . The rapid absorption and avid renal clearance of IFN produce the large fluctuations in IFN semm concentrations that are seen after each dose (Figure 1). UN s therapeutic efficacy is Mmited by its relatively brief residence time in a patient s circulation. Indeed, the amount of IFN left in the body after 24 hours is so insignificant that the three times weekly regimen is unlikely to maintain semm levels that are required for adequate antiviral or immunomodulatory activity. 

Lalezari JP, Patel IH, Zhang X, Dorr A, Hawker N, Siddique Z, Kolis SJ, Kinchelow T. Influence of subcutaneous injection site on the steady-state pharmacokinetics of enfuvirtide (T-20) in HTV-1-infected patients. J Clin Virol 2003 28(2) 217-22. 

M. Apley, M. Wray and D. Armstrong, Subcutaneous injection site comparison of two multiple valent clostridial bacterin/toxoids in feedlot cattle, Agri-Practice, 1994, 15, 9-12. 

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