The main ingredient of Jingo is sildenafil, and the main side effects after using the drug are headache, flushing and indigestion. When using Jingo, you must be careful not to take it with grapefruit juice, because grapefruit juice will increase the toxic effects of sildenafil. In addition, if the erection lasts longer than 4 hours, it is important to seek immediate medical attention as it may cause damage to the penile tissue and even permanent erectile dysfunction. It is possible to experience dizziness, or fainting like this during the use of the drug, so if you are sitting or lying down, be sure to get up slowly to prevent fainting. It is recommended to take this medication one hour before sexual activity. If the diet you eat is high in fat, it may also delay the onset of sildenafil.