A Brief Introduction to Sildenafil Citrate
Molecular Formula:C28H38N6O11S
Molecular Weight:666.7
CAS: 171599-83-0
Appearance:White to beige powder
Regular commercial package: 25kg/drum
What is Sildenafil Citrate?
- It is a highly selective phosphodiesterase-5 (PDE5) inhibitor.
- Sildenafil Citrate appears as a white powder, is slightly soluble in water, readily soluble in ethanol, and is slightly hygroscopic. It should be stored in a sealed, dry, and light-protected environment.
- It is mainly used in the production of commonly used tablets or other special formulations (such as suspensions or dry suspensions) for the treatment of ED and PAH.
- In recent years, sildenafil citrate has also been used in clinical research in other fields, such as high-altitude pulmonary edema and Raynaud’s phenomenon.

Highassay’s Sildenafil Citrate
Highassay, as a supplier of Sildenafil Citrate raw materials from China, offers products with a purity of 99% or higher. Highassay’s products adhere to the strictest quality control standards, ensuring reliable raw materials. We have GMP-compliant factories and a stable supply capacity. If you require large quantities, we will offer you the most competitive prices.
If you are a manufacturer of Sildenafil Citrate preparations, you can purchase high-quality active pharmaceutical ingredients from Highassay, add excipients (such as starch, lactose, film coating, etc.), and go through a series of manufacturing processes to produce high-quality, marketable finished pharmaceutical products.
For purchasing Sildenafil Citrate, choose Highassay!
Dosage forms of Sildenafil Citrate
If you have any questions about processing Sildenafil Citrate, Highassay’s R&D team is here to help.
Sildenafil Citrate Tablets
Sildenafil Citrate Orally Disintegrating Tablets
Sildenafil Citrate Suspension
Sildenafil Citrate Dry Suspension
Uses of Sildenafil Citrate
- Treatment of erectile dysfunction in men.
- Treating pulmonary hypertension, a life-threatening cardiovascular disease.
- Under the evaluation of specialist physicians (rheumatology and immunology, urology, etc.), it can also be used for certain conditions for which it is not officially approved, such as severe Raynaud’s phenomenon and digital ulcers caused by connective tissue diseases like scleroderma; and for the prevention and adjunctive treatment of high-altitude pulmonary edema.


Dosage of Sildenafil Citrate
The following distinctions exist depending on the purpose:
For use in erectile dysfunction (ED): 50 or 100 mg (taken as needed, higher dose if necessary, approximately 1 hour before sexual activity).
For use in Pulmonary Arterial Hypertension (PAH): 20 mg once, three times a day (low dose, long-term, regular administration).
*The dosage regimens for these two uses absolutely cannot be confused or interchanged. Sildenafil Citrate, as a prescription medication, can lead to two completely opposite and serious consequences if used incorrectly: ineffectiveness or severe poisoning, even endangering life.
Side effects of Sildenafil Citrate
- It should not be used in combination with nitrate medications, as both work by dilating blood vessels. Using them together may lead to a rapid drop in blood pressure, resulting in serious consequences such as fainting and shock.
- Common side effects after taking the medication usually include headache, facial flushing, and nausea; a small number of people may experience blurred vision.
- Patients of different age groups may exhibit different responses and side effects to medications, which are usually temporary.

The mechanism of action of Sildenafil Citrate
For erectile dysfunction (ED): Sildenafil Citrate works by inhibiting the activity of the PDE5 enzyme, reducing the breakdown of cGMP. When sexual stimulation occurs, the levels of cGMP in the body increase, causing the blood vessels in the corpus cavernosum of the penis to dilate. This increases arterial blood flow while simultaneously restricting venous blood outflow, leading to engorgement of the corpus cavernosum, increased pressure, and penile erection.
For Pulmonary Arterial Hypertension (PAH): Sildenafil Citrate reaches the lungs via the bloodstream, selectively inhibiting PDE5 enzymes in the pulmonary blood vessels. This prevents the breakdown of cGMP, significantly increasing and maintaining its levels, thereby dilating the pulmonary arteries, reducing blood flow resistance, and lowering pulmonary artery pressure.





