The most important thing to do when you always feel sick and repeatedly suspect and check again and again is to treat it promptly. First of all, you can consider taking drugs for treatment, taking selective 5-hydroxytryptamine reuptake inhibitors, such as fluoxetine, paroxetine, sertraline, etc. You can also take venlafaxine, duloxetine, Dexedrine for treatment, these drugs will have obvious effects after 2-4 weeks of taking. Next, you can also consider psychotherapy, such as cognitive-behavioral therapy, humanistic therapy, psychoanalytic therapy, behavioral therapy, these psychotherapy methods are very effective. Then you should also try to adjust their own mindset, build self-confidence, or in their own always nervous, anxious about health problems, learn to do relaxation training, such as imagining their own good life, imagine themselves in a beautiful environment, are sunbathing on the beach or on the prairie to breathe fresh air, look at the beautiful scenery, etc., only then can reduce the excessive concern about their health. These methods combined to do, generally will have very good results.