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Organic nitrates stop a labelled sildenafil swallow, including the 100 mg figure
4 min readReviewed 21 August 2026. Updated
At a glance
Page typeNote
Print10/100
ReviewerCamille Rousseau, MD
Do not add a second PDE5 tablet on the same day as this swallow.
01Do not combine two PDE5 products
The carton prints two milligrams on a single swallow.
Do not combine a labelled PDE5 inhibitor with other PDE5 inhibitors or other ED therapies. The maximum recommended dosing frequency on the U.S. sildenafil label is once per day. The maximum recommended dosing frequency on the U.S. tadalafil label is once per day.
Sexual stimulation is required on both U.S. labels.
02The 100 milligram figure on the U.S. sildenafil label
The maximum recommended dose of sildenafil is 100 mg. The recommended starting dose of sildenafil for most patients is 50 mg. VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity.
Sildenafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently.
03The 10 milligram figure on the U.S. tadalafil label
The recommended starting dose of tadalafil for use as needed is 10 mg, taken prior to anticipated sexual activity. The dose may be increased to 20 mg or decreased to 5 mg. Tadalafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently.
How to cite this page - Vancouver style
Halo Medix Medicines Reference. Organic nitrates stop a labelled sildenafil swallow, including the 100 mg figure [Internet]. Montreal: Halo Medix; 21 August 2026 [cited 2026 Aug 21]. Available from: https://halomedix.com/notes/sildalist-combo-caution/
('Readers around Montreal asked about the Sildalist 10/100 carton. ', 'Answers follow the separate U.S. Viagra and Cialis labels.')
Laurent Pelletier, Centre-Sud asks
Is Sildalist 10/100 a U.S. approved pair?
Reply from our reviewer
Do not combine a labelled PDE5 inhibitor with other PDE5 inhibitors or other ED therapies. The maximum recommended dosing frequency on each U.S. label is once per day.
Nadia Côté, Île-des-Soeurs asks
What does 100 mean on the U.S. sildenafil label?
Reply from our reviewer
The maximum recommended dose of sildenafil is 100 mg. The recommended starting dose of sildenafil for most patients is 50 mg. VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity. Sexual stimulation is required. Sildenafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently.
Omar Farhat, Saint-Léonard asks
What does 10 mean on the U.S. tadalafil label?
Reply from our reviewer
The recommended starting dose of tadalafil for use as needed is 10 mg, taken prior to anticipated sexual activity. The dose may be increased to 20 mg or decreased to 5 mg. The maximum recommended dosing frequency is once per day. Tadalafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently.
Brigitte Lavoie, Westmount-adjacent asks
Can I add a Cialis 20 mg after Sildalist the same night?
Reply from our reviewer
Do not combine a labelled PDE5 inhibitor with other PDE5 inhibitors or other ED therapies. The maximum recommended dosing frequency on each U.S. label is once per day.
Hélène Martel, Westmount asks
What hour window is written on the U.S. sildenafil label?
Reply from our reviewer
VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity. Most studies assessed the efficacy of VIAGRA approximately 60 minutes post dose. The maximum recommended dose of sildenafil is 100 mg. The recommended starting dose of sildenafil for most patients is 50 mg. Sexual stimulation is required. Sildenafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently.
Olivier Saadi, Saint-Laurent asks
How long after as-needed tadalafil was function still better than placebo?
Reply from our reviewer
Tadalafil for use as needed was shown to improve erectile function compared to placebo up to 36 hours following dosing. The recommended starting dose of tadalafil for use as needed is 10 mg. The dose may be increased to 20 mg or decreased to 5 mg. The maximum recommended dosing frequency is once per day. Sexual stimulation is needed. Tadalafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently.
Camille Traoré, Montréal-Nord asks
Is Sildalist 10/100 written for women on a U.S. insert?
Reply from our reviewer
VIAGRA is not indicated for use in females. Tadalafil is not indicated for use in females. Do not combine a labelled PDE5 inhibitor with other PDE5 inhibitors or other ED therapies.
Julie Bélanger, Ahuntsic asks
What storage lines sit on the two U.S. cartons?
Reply from our reviewer
Store CIALIS at 25 C (77 F); excursions permitted to 15 to 30 C (59 to 86 F). Keep out of reach of children. Read the carton that arrived if the printed range differs. Keep out of reach of children. Do not combine a labelled PDE5 inhibitor with other PDE5 inhibitors or other ED therapies.
Pierre-Luc Gagnon, Anjou asks
What half-life is written on the U.S. sildenafil label?
Reply from our reviewer
Both sildenafil and the metabolite have terminal half lives of about 4 hours. The pharmacokinetics of sildenafil are dose-proportional over the recommended dose range. The maximum recommended dose of sildenafil is 100 mg. The recommended starting dose of sildenafil for most patients is 50 mg. VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity. Sexual stimulation is required on the U.S. sildenafil label.
