Loading…
UPH-SILDENAFIL is a brand name for Sildenafil, supplied as a tablet. The medicine, its uses, side effects and dosage are the same regardless of brand.
Used for: AND CLINICAL USE ................................................................................. 3 CONTRAINDICATIONS ................................................................................................... 3 WARNINGS AND PRECAUTIONS…
Verbatim from this product's HC label. Tap a section to expand.
). The concomitant use of the potent cytochrome P-450 3A4 inhibitor, ritonavir is associated with a 1000% (11-fold) increase in plasma levels (AUC) of sildenafil. Given the extent of the interaction with patients receiving concomitant therapy with ritonavir, it is recommended not to exceed a maximum single dose of 25 mg of sildenafil in a 48-hour period (see WARNINGS AND PRECAUTIONS).
Administration To be taken as needed approximately 30 – 60 minutes before sexual activity. 5 hour to 4 hours before sexual activity. The maximum recommended dosing frequency is once per day. OVERDOSAGE In studies with healthy volunteers of single doses of up to 800 mg, adverse events were similar to those seen at lower doses but incidence rates and severities were increased.
In cases of overdose, standard supportive measures should be adopted as required. Renal dialysis is not expected to accelerate clearance as sildenafil is highly bound to plasma proteins and not eliminated in the urine. Treatment of Priapism Patients should be instructed to report any erections persisting for more than 4 hours to a physician.
The treatment of priapism/prolonged erection should be according to established medical practice. Physicians may refer to two suggested protocols for detumescence presented below. Detumescence Protocols 1) Aspirate 40 to 60 mL blood from either left or right corpora using vacutainer and holder for drawing blood.
Patient will often detumesce while aspirating. Apply ice for 20 minutes post aspiration if erection remains. If procedure 1) is unsuccessful, then try procedure 2). 2) Put patient in supine position. 05%). 2 mL (50-100 μg) into the corpora every 2 to 5 minutes, until the detumescence occurs.
The occasional patient may experience transient bradycardia and hypertension when given phenylephrine injections, therefore monitor patient’s blood pressure and pulse every 10 minutes. Patients at risk include those with cardiac arrhythmias and diabetes.
Refer to the prescribing information for phenylephrine before use. Do not give phenylephrine to patients on MAO inhibitors. When phenylephrine is used within the first 12 hours of erection, the majority of patients will respond. If procedure 2) is unsuccessful, then try procedure 3).
For management of a suspected drug overdose, contact your regional Poison Control Centre immediately. Page 17 of 46 3) If the above measures fail to detumesce the patient, a urologist should be consulted as soon as possible, especially if the erection has been present for many hours.
Not medical advice. Always read the patient information leaflet and follow your prescriber or pharmacist.
Other brands of Sildenafil in Canada.
Know a brand we are missing in Canada? Suggest a brand →
Brand names are compiled from public regulatory records for active-ingredient mapping only. Drugvu is not affiliated with any manufacturer. This is not medical advice.
If priapism is not treated immediately, penile tissue damage and/or permanent loss of potency may result. ACTION AND CLINICAL PHARMACOLOGY Mechanism of Action Sildenafil citrate is a cGMP-specific phosphodiesterase type 5 (PDE5) inhibitor, used for the treatment of male erectile dysfunction.
The physiological mechanism responsible for erection of the penis involves the release of nitric oxide (NO) in the corpus cavernosum in response to sexual stimulation. Nitric oxide then activates the enzyme guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP), producing smooth muscle relaxation in the corpus cavernosum and allowing inflow of blood.
Sildenafil has no direct relaxant effect on isolated human corpus cavernosum, but enhances the effect of NO by inhibiting PDE5, which is responsible for the biodegradation of cGMP in the corpus cavernosum. When sexual stimulation causes local release of NO, inhibition of PDE5 by sildenafil produces increased levels of cGMP in the corpus cavernosum, resulting in smooth muscle relaxation and increased inflow of blood to the corpus cavernosum.
Sildenafil, at recommended doses, has no effect in the absence of sexual stimulation. Studies in vitro have shown that sildenafil has between 10 and 10,000-fold greater selectivity for PDE5 than for other phosphodiesterase isoforms namely PDEs 1, 2, 3, 4, and 6 and greater than 700-fold effect on PDE7-PDE11.
In particular, sildenafil has greater than 4,000-fold selectivity for PDE5 over PDE3, the cAMP-specific phosphodiesterase isoform involved in the control of cardiac contractility. Sildenafil is about 10-fold as potent for PDE5 compared to PDE6, an isoenzyme found in the retina; this lower selectivity is thought to be the basis for colour vision abnormalities observed with higher doses or plasma levels of sildenafil (see WARNINGS AND PRECAUTIONS, DETAILED PHARMACOLOGY).
PDE5 is also found in lower concentrations in platelets, vascular and visceral smooth muscles, and skeletal muscle. The sildenafil-induced inhibition of PDE5 in these tissues appears to be the basis for the enhanced platelet antiaggregatory activity of nitric oxide observed in vitro, and inhibition of platelet thrombus formation in vivo, and peripheral arterial-venous dilation in vivo (see WARNINGS AND PRECAUTIONS).
3 mm Hg). The decrease in blood pressure was most notable approximately 1-2 hours after dosing. The effects are not related to dose or plasma levels. Larger effects were recorded among patients receiving concomitant nitrates (see CONTRAINDICATIONS).
Page 18 of 46 Effects of Sildenafil Citrate on Cardiac Parameters:
Single oral doses of sildenafil citrate up to 100 mg in healthy volunteers produced no clinically relevant effects on ECG.
Effects of Sildenafil Citrate on Erectile Response:
Sildenafil citrate was studied in clinical trials of various designs. In fixed-dose clinical trials, 62%, 74%, and 82% of patients on 25 mg, 50 mg and 100 mg of sildenafil citrate, respectively, reported an improvement in their erections, […]