that works best for you. Your Doc should work with you on this.
Assuming your Doc can safely prescribe these meds, note that although they all do the same thing in the same manner, they have some different characteristics:
FOOD AND DOSE TIMING (CONVENIENCE AND EFFECTIVENESS):
"As with sildenafil, a high-fat meal delays the absorption of vardenafil by up to 1 h and decreases the maximal concentration of vardenafil by approximately 20% compared with the fasted state.[19]"
"None of the three PDE5 inhibitors act immediately. Most studies have illustrated that the drugs have an onset of action between 30 and 60 min, but the rate of onset of each drug varies between individuals. The prescribing information for sildenafil recommends dosing 60 min before sexual activity,[21,22]"
"Sildenafil and vardenafil both have a terminal half-life of approximately 4 h,[15,16] and tadalafil has a half-life of 17.5 h."
So if you take your Levitra near a meal, it may take up to 2 hrs to reach maximum absorption, may not reach the intended peak concentrations, and will cease to work in something less than the 4 hr window expected. Cialis may be a good option for "consistency of action", as it is unaffected by food, is active within 20 mins and remains active for an extended time.
Cialis has dosing regimens for daily use and "as needed".
Daily dose is typically 5 mg for a healthy individual, and 2.5 mg for folks who respond at a lower dose or those with certain health risks or who are taking other drugs that may interact.
The "as needed" dose is typically started at 10 mg every 72 hrs, and may be increased up to 20 mg every 72 hrs. Similarly, a 5 mg or 7.5 mg dose may be fine for those who respond to a lower dose.
The other ED drugs (Viagra - sildenafil citrate; Levitra - vardenafil) both have shorter terminal half-lives (windows of effectiveness) of around 4-5 hours, while Cialis has a half-life of about 72 hrs. Cialis is also more selective for the PDE-5 enzyme (the target of action for each ED med), has a shorter onset of action (15 mins versus 30-60 minutes) and its absorption and effectiveness is unaffected by food intake - unlike the other two ED meds, which are significantly affected by timing of meals and diet. In quite a few studies, Cialis was chosen over either Viagra or Levitra by the large majority of patients who had tried more than 1 ED drug.
REFRACTORY PERIOD:
After ejaculating, your body will produce a hormonal cascade. Oxytocin and Prolactin are released, cholinesterase and norepinephrine are released, etc... This cascade leads to an erectile refractory period, that prevents a repeat erection until the pre-ejaculatory hormonal milieu is restored. The average for all males is about 30 minutes, but can range from almost no time at all to 20 hours for the average man in his 70's.
There are no approved drugs in the US for reducing refractory periods, but cabergoline (cabaser) has been used off-label to reduce prolactin let-down after ejaculation and thus to shorten refractory period. Yohimbine (Rauwolscine) has also been used to block alpha-adregenergic receptors and reduce adregenergic vasoconstriction. Alpha blockers such as Flomax, Cardura, Uroxatraal and Rapaflo may also be helpful in a similar manner - although again, they are not approved for this use and may cause ejaculatory issues (retrograde ejaculation, primarily).
DELAYED EJACULATION:
I could not locate anything that clearly established a link between either premature or delayed orgasm/ejaculation associated with ED drugs. Typically, ejaculatory latency disorders are related to other types of medications (antidepressants being notorious for this), performance anxiety, lack of psychosexual stimulation (the "too much porn syndroome") and other factors unrelated to the ED drugs per se.
Not the Medical kind of Doc. Just offering some info to discuss with your GP or Urologist
