Preferred Sample Type
Suitable Specimen Types
- Serum
- EDTA Plasma
- Li Hep Plasma
Specimen Transport
UsualSample Processing in Laboratory
Centrifuge and place in toxicology box in cold room.Sample Preparation
CentrifugeTurnaround Time
3 working daysSample Stability
4 ºCSildenafil
General Information
Sildenafil (Revatio, Viagra) is an inhibitor of cyclic GMP phosphodiesterase, originally developed as an antihypertensive agent, but now used frequently for the treatment of erectile dyfunction. The drug is supplied as the citrate salt in 20 - 100 mg tablets for oral administration. The usal adult dosage in 20 mg thrice daily in hypertensive patients and 25 - 100 mg no more than once daily in erectile dysfunction patients.
Adverse effects associated with sildenafil therapy include headache, flushing, blurred vision, dypepsia and musculoskeletal pain. The drug may potentiate the hypotensive effects of co-administered organic nitrates. Overdosage may result in hypotension, tachycardia and cardiac arrest.
Patient Preparation
For TDM, sample should be taken prior to dose. If toxicity is suspected, take sample at earliest opportunity
Notes
Please avoid use of gel seperator tubes.
Please note this assay is not currently UKAS accredited
Reference Range
0.05 - 0.5 mg/L
Specifications
- EQA Scheme?: Yes
- EQA Status: LGC QUARTZ, LGC CLIN TOX