Understanding Sildenafil: Clinical Information
How Sildenafil Works According to BNF Guidelines
Sildenafil belongs to a class of medications called PDE5 inhibitors, as detailed in the British National Formulary. It works by blocking the phosphodiesterase type 5 enzyme, which increases blood flow to the penis during sexual arousal. Patients can choose between generic sildenafil or branded Viagra at EverydayMeds, as both contain the same active ingredient and work identically.
BNF Dosage Recommendations
The BNF recommends starting with sildenafil 50mg, taken approximately one hour before sexual activity. Depending on effectiveness and tolerability, the dose may be adjusted to 25mg or increased to a maximum of 100mg. Only one dose should be taken within any 24-hour period. Both generic sildenafil and Viagra follow these same dosing guidelines.
Contraindications and Safety Warnings
The BNF clearly states that sildenafil must not be used with nitrates such as GTN spray or isosorbide medications due to dangerous blood pressure drops. Other contraindications include severe heart disease, recent heart attack or stroke within six months, severe liver impairment, and very low blood pressure. Patients taking riociguat should also avoid sildenafil.
Clinical Assessment Requirements
As outlined in BNF guidance, sildenafil requires prescription following proper clinical assessment. This evaluation includes cardiovascular health review, current medications check, and medical history assessment. EverydayMeds ensures all patients complete this essential safety screening with qualified UK prescribers before accessing either generic sildenafil or branded Viagra options.
Side Effects and Monitoring
Common side effects listed in the BNF include headache, facial flushing, indigestion, and nasal congestion. Serious but rare side effects requiring immediate medical attention include prolonged erections lasting over four hours, sudden vision loss, or chest pain. Regular monitoring may be recommended for patients with cardiovascular conditions or those taking multiple medications alongside sildenafil treatment.












