Procain penicillin

There was added to 250 ml of a concentrated butyl acetate extract containing 74,000 units of the acid form of penicillin per ml, 50 ml of a butyl acetate solution containing 0.238 g per ml of procaine base. The solution was agitated for one hour. The precipitate which formed was very gummy and not in the form of discrete crystals. This precipitate was crystallized by scratching the side of the vessel and agitating further. After this treatment 18.25 g of crystalline procaine penicillin was obtained which assayed 1010 units per mg representing a yield of 99.6% of the activity contained in the concentrated extract. 

Examples of reversible breakdown of structure have been reported for procaine penicillin dispersions (7), for model systems of calcium carbonate in polybutene ( ), and for numerous other systems. During shear the particles are forced into contact with each other with sufficient kinetic energy to overcome any natural barrier against their displacement of a lyosphere around each individual particle. A dispersion which is inherently stable can thus be forced by shear into a condition of instability. 

Aqueous crystalline Penicillin G, 3-4 million units IV every 4 hours for 10-14 days or procaine Penicillin G, 2.4 million units IM q.d., plus 500iug of probenecid poq i.d. for 10 14 days... 

Procaine penicillin G 2.4 million units administered intramuscularly once daily, plus probenecid 500 mg orally four times daily for 10 to 14 days. 

TABLE 77-1. Benzathine and Procaine Penicillin G Informational Chart3... 

Alternatives Procaine penicillin 0.6 to 0.9 million units intramuscularly for 10 to 14 days, or ceftriaxone 1 g daily intramuscularly or intravenously for 8 to 10 days. 

Symptomatic neonates 50,000 U/kg of aqueous crystalline penicillin G every 12 hours intramuscularly for the first 7 days of life, then every 8 hours for 3 days, or procaine penicillin G 50,000 IU/kg intramuscularly as a single dose daily for 10 days... 

If the solubility of a drug is to be reduced to enhance stability or to prepare a suspension, the for-mulator may prepare water-insoluble salts. A classic example is procaine penicillin G, the decreased solubility (7 mg/mL) of which, when compared with the very soluble penicillin G potassium, is utilized to prepare stable parenteral suspensions. Another alternative to preparing an insoluble drug is to use the parent acidic or basic drug and to buffer the pH of the suspension in the range of minimum solubility. 

In the first example, procaine penicillin, an aqueous vehicle containing the soluble components (such as lecithin, sodium citrate, povidone, and polyoxyethylene sorbitan monooleate) is filtered through a 0.22 pm membrane filter, heat sterilized, and transferred into a presterilized mixing-filling tank. The sterile antibiotic powder, which has previously been produced by freeze-drying, sterile crystallization, or spray-drying, is aseptically added to the sterile solution while mixing. After all tests have been completed on the bulk formulation, it is aseptically filled. 

Aqueous procaine penicillin G 2.4 million units IM daily plus probenecid 500 mg orally four times daily, both for 10-14 days 6 Aqueous crystalline penicillin G 50,000 units/kg IV every 12 hours during the first 7 days of life and every 8 hours thereafter for a total of 10 days or... 

Procaine penicillin G 50,000 units/ kgIM daily for 10 days Doxycycline 100 mg orally two times daily for 2 weeks 7 or... 

Procaine penicillin C 600,000 units intramuscularly eveiy 12 hours... 

As streptococcal cellulitis is indistinguishable clinically from staphylococcal cellulitis, administration of a semisynthetic penicillin (nafrillin or oxacillin) or first-generation cephalosporin (cefazolin) is recommended until a definitive diagnosis, by skin or blood cultures, can be made (Table 47-4). If documented to be a mild cellulitis secondary to streptococci, oral penicillin VK, or intramuscular procaine penicillin may be administered. More severe streptococcal infections should be treated with IV antibiotics (such as ceftriaxone 50 to 100 mg/kg as a single dose). 

Penicillin VK 0.5 g orally every 6 hours4 or procaine penicillin G 600,000 units IM every 8-12 hours4... 

Since 1977, the Food and Drug Adminstration (FDA) has been considering a ban on the subtherapeutic use of procaine penicillin and tetracyclines in animal feeds. These antibiotics are used in both humans and animals, and any use of an antibiotic that is prescribed for humans presents some risk to human health, whether the use is for humans, animals, or other purposes. The risk is that pathogenic or disease-causing bacteria may develop a strain that resists that antibiotic. The resistant strain of the pathogen then may cause human disease that cannot be treated by this antibiotic. 

Neurosyphilis - Aqueous procaine penicillin G, 2 to 4 million units/day IM plus... 

Procaine penicillin G, 2.4 million units/day IM plus probenecid 500 mg orally 4 times/day, both for 10 to 14 days. Many recommend benzathine penicillin G, 2.4 million units IM once/wk for up to 3 wk following completion of this regimen. 

Procaine penicillin modestly extends the duration of action of benzylpenicillin. The dose is limited by the volume that can be administered intramuscularly. If the insoluble penicillins are by accident injected intravenously potentially life-threatening reactions can result. 

Depot intramuscular formulations of penicillin G, including procaine penicillin and benzathine penicillin, have decreased solubility, delayed absorption, and a prolonged half-life. Drug concentrations are detectable 24 hours after injection of procaine penicillin, and low levels of benzathine penicillin (0.003 units/mL) are detectable 4 weeks after injection. 

Gonococcal infection Procaine penicillin along with probenecid can be used. 

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