Fatal bone-marrow suppression, apparently dose related, can occur with guanidine.
Safe use of guanidine hydrochloride in pregnancy has not been established. Therefore, the benefits of therapy must be weighed against the potential hazards. Because guanidine is excreted in milk, patients on this drug should discontinue breast-feeding.
Since there is inadequate experience in children who have received this drug, safety and efficacy in children have not been established.
Baseline blood studies should be followed by frequent red and white blood cell and differential counts. The drug should be discontinued upon appearance of bone-marrow suppression. Concurrent therapy with other drugs that may cause bone-marrow suppression should be avoided.
Renal function may be affected in some patients receiving guanidine. Patients should therefore have regular urine examinations and serum creatinine determinations while taking this drug.
Physicians should be given adequate precautions pertaining to the gastrointestinal side effects and the possibility of induced behavior disorders.
Treatment should not be continued longer than necessary.