Are there any side effects of Viagra?

Generally speaking, Viagra usually refers to sildenafil citrate tablets, which have certain side effects. Possible side effects include headache, facial flushing, indigestion, visual disturbances, dizziness, and others. If this medication is needed, it should be taken under the guidance of a physician. Detailed explanations are as follows:

1. Headache

Sildenafil citrate tablets may promote blood vessel dilation, including in the cerebral vessels. When cerebral blood vessels dilate, surrounding nerve endings may be stimulated, leading to headache. Usually, the severity of headache varies among individuals and is mostly mild to moderate, gradually subsiding after the drug has been metabolized.

2. Facial Flushing

This medication can increase the release of nitric oxide in the body, subsequently activating guanylate cyclase, which elevates cyclic guanosine monophosphate (cGMP) levels, causing relaxation of vascular smooth muscle. Facial blood vessels are abundant and superficial; when smooth muscles relax, the blood vessels dilate, increasing blood flow and resulting in facial flushing.

3. Indigestion

After entering the body, sildenafil citrate tablets may affect normal gastrointestinal motility and secretion of digestive fluids. Disordered gastrointestinal motility and imbalanced secretion of digestive fluids can impair digestion and absorption of food in the gastrointestinal tract, thereby causing indigestion with symptoms such as stomach pain, bloating, and nausea.

4. Visual Disturbances

Phosphodiesterase (PDE) isoenzymes are present in the retina. While inhibiting PDE5 in the corpus cavernosum of the penis, sildenafil citrate tablets may also affect PDE on the retina, interfering with visual signal transmission and resulting in visual abnormalities such as blurred vision and increased light sensitivity.

5. Dizziness

The vasodilation caused by sildenafil not only occurs on the skin and internal organs but also affects the blood vessels of the inner ear. Changes in inner ear blood vessels can interfere with the balance function of the inner ear, affect the transmission of nerve signals to the brain, cause the brain to misinterpret the body's sense of balance, and subsequently lead to a sensation of dizziness.

Avoid consuming large amounts of alcohol and high-fat foods before and after taking sildenafil. Alcohol and high-fat foods can influence the drug's metabolism and absorption and may exacerbate side effects, affecting health. If severe discomfort or persistent side effects occur after taking sildenafil, immediate medical attention should be sought. Prompt medical care ensures accurate diagnosis and treatment, preventing deterioration of the condition.