The generic name of Viagra is sildenafil citrate tablets, eating sildenafil citrate tablets after coitus may have chills, related to adverse drug reactions, may also be due to coitus suffered. 1. Adverse drug reactions: after taking sildenafil citrate tablets, supraventricular arrhythmia may occur in some people, which can easily lead to sudden cardiac death, which can induce panic, rapid heartbeat, chills and other symptoms. 2. Exhaustion from coitus: coitus is too frequent or coitus lasts too long, leading to excessive fatigue, excessive sweat secretion, consuming a lot of heat, which may lead to cold body. When taking sildenafil citrate tablets orally, you should know that it is forbidden if you are allergic to the ingredients of the drug or have liver or kidney insufficiency. Dizziness, headache, flushing, dyspepsia and other symptoms may occur after taking the drug, usually after stopping the drug, the effect of the drug is exerted and the symptoms can be relieved by themselves. If you need to take sildenafil citrate tablets orally, it is recommended to follow the doctor’s instructions to avoid unauthorized use of the drug, such as any adverse reactions during the use of the drug, you need to consult a doctor in a timely manner.