Patients with hypertension should not receive or should minimize their intake of caffeine. Patients with diabetes mellitus should not receive or should minimize their intake of caffeine. Although the effects are mild, caffeine can raise blood sugar. Patients with thyroid disease, especially hyperthyroidism, should not receive or should minimize their intake of caffeine. The stimulatory effects of caffeine can be augmented in hyperthyroidism.
Caffeine can stimulate gastric secretions.
Patients with peptic ulcer disease should not receive or should minimize their intake of caffeine because the condition can be aggravated. Caffeine should be used cautiously, if at all, during pregnancy and during breast-feeding. Although only small amounts are secreted in milk, caffeine can accumulate in the neonate. Fetal arrhythmias have been reported when caffeine was consumed during pregnancy. The CNS-stimulating actions of caffeine can be additive with other CNS stimulants or psychostimulants.