The DSM-IV describes pathological gambling as a chronic condition with an insidious course. However, several extant studies characterize pathological and problem gambling as fluctuating over time. The present analyses expand on previous reports by evaluating changes in pathological gambling symptoms across the lifetime. DSM-IV pathological gambling symptoms were assessed retrospectively to derive diagnoses and capture changes in symptoms over time using the Lifetime Gambling History (LGH) in a sample of 1343 middle aged males from the Vietnam Era Twin (VET) Registry. Two to four weeks after initial assessment, 196 participants were re-assessed to determine test–retest reliability of the LGH. A greater number of lifetime symptoms was associated with a higher number of changes in gambling patterns. Fluctuations in pathological gambling symptoms were common among individuals who reported two or more gambling phases, with decreases in symptoms reported as frequently as increases. Reliability data revealed high reliability in reports of pathological gambling symptom endorsement and age of symptom onset. Results are consistent with findings from community based studies that describe the course of problem gambling behaviors as changing over time. Evidence is also provided for the utility of the LGH in assessing lifetime pathological gambling symptoms.