PRECAUTIONS
General
Prescribing Bicillin C-R in the absence of a proven or strongly suspected bacterial infection or a
prophylactic indication is unlikely to provide benefit to the patient and increases the risk of a
development of drug-resistant bacteria.
Penicillin should be used with caution in individuals with histories of significant allergies and/or
asthma.
Care should be taken to avoid intravenous or intra-arterial administration, or injection into or near
major peripheral nerves or blood vessels, since such injections may produce neurovascular
damage. (See WARNINGS, and DOSAGE AND ADMINISTRATION sections.)
A small percentage of patients are sensitive to procaine. If there is a history of sensitivity, make
the usual test: Inject intradermally 0.1 mL of a 1 to 2 percent procaine solution. Development of
an erythema, wheal, flare, or eruption indicates procaine sensitivity. Sensitivity should be treated
by the usual methods, including barbiturates, and procaine penicillin preparations should not be
used. Antihistamines appear beneficial in treatment of procaine reactions.
The use of antibiotics may result in overgrowth of nonsusceptible organisms. Constant
observation of the patient is essential. If new infections due to bacteria or fungi appear during
therapy, the drug should be discontinued and appropriate measures taken.
Whenever allergic reactions occur, penicillin should be withdrawn unless, in the opinion of the
physician, the condition being treated is life-threatening and amenable only to penicillin therapy.
In prolonged therapy with penicillin, and particularly with high-dosage schedules, periodic
evaluation of the renal and hematopoietic systems is recommended.
Laboratory Tests
In streptococcal infections, therapy must be sufficient to eliminate the organism; otherwise, the
sequelae of streptococcal disease may occur. Cultures should be taken following completion of
treatment to determine whether streptococci have been eradicated.
Pregnancy
Reproduction studies performed in the mouse, rat, and rabbit have revealed no evidence of
impaired fertility or harm to the fetus due to penicillin G. Human experience with the penicillins
during pregnancy has not shown any positive evidence of adverse effects on the fetus. There are,
however, no adequate and well-controlled studies in pregnant women showing conclusively that
harmful effects of these drugs on the fetus can be excluded. Because animal reproduction studies
are not always predictive of human response, this drug should be used during pregnancy only if
clearly needed.
Nursing Mothers
Soluble penicillin G is excreted in breast milk. Caution should be exercised when penicillin G
benzathine and penicillin G procaine are administered to a nursing woman.
Carcinogenesis, Mutagenesis, Impairment Of Fertility
No long-term animal studies have been conducted with these drugs.
Pediatric Use
(See INDICATIONS and DOSAGE AND ADMINISTRATION sections.)
Geriatric Use
Clinical studies of penicillin G benzathine and penicillin G procaine did not include sufficient
numbers of subjects aged 65 and over to determine whether they respond differently from
younger subjects. Other reported clinical experience has not identified differences in responses
between the elderly and younger patients. In general, dose selection for an elderly patient should
be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of
decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to
this drug may be greater in patients with impaired renal function (see CLINICAL PHARMACOLOGY). Because elderly patients are more likely to have decreased renal function,
care should be taken in dose selection, and it may be useful to monitor renal function.
REFERENCES
1. SHAW, E.: Transverse myelitis from injection of penicillin. Am. J. Dis. Child., 111:548,
1966.
2. KNOWLES, J.: Accidental intra-arterial injection of penicillin. Am. J. Dis. Child., 111:552,
1966.
3. DARBY, C. et al: Ischemia following an intragluteal injection of benzathine-procaine
penicillin G mixture in a one-year-old boy. Clin. Pediatrics, 12:485, 1973.
4. BROWN, L. & NELSON, A.: Postinfectious intravascular thrombosis with gangrene. Arch.
Surg., 94:652, 1967.
5. BORENSTINE, J.: Transverse myelitis and penicillin (Correspondence). Am. J. Dis. Child.,
112:166, 1966.
6. ATKINSON, J.: Transverse myelopathy secondary to penicillin injection. J. Pediatrics,
75:867, 1969.
7. TALBERT, J. et al: Gangrene of the foot following intramuscular injection in the lateral
thigh: A case report with recommendations for prevention. J. Pediatrics, 70:110, 1967.
8. FISHER, T.: Medicolegal affairs. Canad. Med. Assoc. J., 112:395, 1975.
9. SCHANZER, H. et al: Accidental intra-arterial injection of penicillin G. JAMA, 242:1289,
1979.