Hypoglycemia (low blood sugar): Gliclazide, like other sulfonylurea drugs, can cause symptoms of hypoglycemia (low blood sugar) including dizziness, lack of energy, drowsiness, headache, and sweating have been observed. Weakness, nervousness, shakiness, and numbness or tingling have also been reported. Severe hypoglycemia can result from taking any of the sulfonylurea drugs. Seniors, those with reduced liver or kidney function, and those who are fragile or malnourished are more likely to have low blood sugar with these drugs. Low blood sugar is more likely to occur when food intake is inadequate or after strenuous or prolonged physical exercise. Monitor your blood glucose regularly and keep an emergency glucose (and glucagon kit) available in case you need to increase your blood sugar levels.
Heavy consumption of the essential amino acid lysine (as indicated in the treatment of cold sores) has allegedly shown false positives in some and was cited by American shotputter C. J. Hunter as the reason for his positive test, though in 2004 he admitted to a federal grand jury that he had injected nandrolone.  A possible cause of incorrect urine test results is the presence of metabolites from other AAS, though modern urinalysis can usually determine the exact steroid used by analyzing the ratio of the two remaining nandrolone metabolites. As a result of the numerous overturned verdicts, the testing procedure was reviewed by UK Sport . On October 5, 2007, three-time Olympic gold medalist for track and field Marion Jones admitted to use of the drug, and was sentenced to six months in jail for lying to a federal grand jury in 2000.