SIDE EFFECTS
As with other penicillins, untoward reactions of the
sensitivity phenomena are likely to occur, particularly in individuals who have
previously demonstrated hypersensitivity to penicillins or in those with a
history of allergy, asthma, hay fever, or urticaria.
As with other treatments for syphilis, the
Jarisch-Herxheimer reaction has been reported.
The following have been reported with parenteral
penicillin G:
General: Hypersensitivity reactions including the
following: skin eruptions (maculopapular to exfoliative dermatitis), urticaria,
laryngeal edema, fever, eosinophilia; other serum sickness-like reactions
(including chills, fever, edema, arthralgia, and prostration); and anaphylaxis
including shock and death. Note: Urticaria, other skin rashes, and serum
sickness-like reactions may be controlled with antihistamines and, if
necessary, systemic corticosteroids. Whenever such reactions occur, penicillin
G should be discontinued unless, in the opinion of the physician, the condition
being treated is life-threatening and amenable only to therapy with penicillin
G. Serious anaphylactic reactions require immediate emergency treatment with
epinephrine. Oxygen, intravenous steroids, and airway management, including
intubation, should also be administered as indicated.
Gastrointestinal: Pseudomembranous colitis. Onset
of pseudomembranous colitis symptoms may occur during or after antibacterial
treatment. (See WARNINGS section.)
Hematologic: Hemolytic anemia, leukopenia,
thrombocytopenia.
Neurologic: Neuropathy.
Urogenital: Nephropathy.
The following adverse events have been temporally
associated with parenteral administration of penicillin G benzathine:
Body as a Whole: Hypersensitivity reactions
including allergic vasculitis, pruritus, fatigue, asthenia, and pain;
aggravation of existing disorder; headache.
Cardiovascular: Cardiac arrest; hypotension;
tachycardia; palpitations; pulmonary hypertension; pulmonary embolism;
vasodilation; vasovagal reaction; cerebrovascular accident; syncope.
Gastrointestinal: Nausea, vomiting; blood in
stool; intestinal necrosis.
Hemic and Lymphatic: Lymphadenopathy.
Injection Site: Injection site reactions including
pain, inflammation, lump, abscess, necrosis, edema, hemorrhage, cellulitis,
hypersensitivity, atrophy, ecchymosis, and skin ulcer. Neurovascular reactions
including warmth, vasospasm, pallor, mottling, gangrene, numbness of the
extremities, cyanosis of the extremities, and neurovascular damage.
Metabolic: Elevated BUN, creatinine, and SGOT.
Musculoskeletal: Joint disorder; periostitis;
exacerbation of arthritis; myoglobinuria; rhabdomyolysis.
Nervous System: Nervousness; tremors; dizziness;
somnolence; confusion; anxiety; euphoria; transverse myelitis; seizures; coma.
A syndrome manifested by a variety of CNS symptoms such as severe agitation
with confusion, visual and auditory hallucinations, and a fear of impending
death (Hoigne's syndrome), has been reported after administration of penicillin
G procaine and, less commonly, after injection of the combination of penicillin
G benzathine and penicillin G procaine. Other symptoms associated with this
syndrome, such as psychosis, seizures, dizziness, tinnitus, cyanosis,
palpitations, tachycardia, and/or abnormal perception in taste, also may occur.
Respiratory: Hypoxia; apnea; dyspnea.
Skin: Diaphoresis.
Special Senses: Blurred vision; blindness.
Urogenital: Neurogenic bladder; hematuria;
proteinuria; renal failure; impotence; priapism.
DRUG INTERACTIONS
Tetracycline, a bacteriostatic antibiotic, may antagonize
the bactericidal effect of penicillin, and concurrent use of these drugs should
be avoided.
Concurrent administration of penicillin and probenecid
increases and prolongs serum penicillin levels by decreasing the apparent
volume of distribution and slowing the rate of excretion by competitively
inhibiting renal tubular secretion of penicillin.