Few things are morning important to your penile health than those morning
erections. Why? Oxygenation. Oxygenation. Oxygenation.
I get emails all the time from men that have lost their morning erections for
months or even years. This is a tragic situation, because morning
erections, through oxygenation, help maintain healthy erectile tissues. Without
that oxygenation, researchers have noted that "fibrosis" sets in, which means a
hardening and aging of the structures. 
This is why I insist that men, if they no longer have morning erections, must
somehow, someway make sure they get several erections during the day. By the
way, this is one of the reasons that sex is so good for males: it
literally helps to maintain their sex life. "Use it or lose it" as they
Morning erections, or the lack thereof, can be a good way to distinguish if you
have psychological (or psychogenic) erectile dysfunction. The idea is that
if you can achieve an erection by any means, nightime or otherwise, then your
issue is probably not physical (organic). In fact, this has been used by
diagnosticians for literally decades as an excellent tool.  In fact, one
study noted that "the single best predictor was the presence or absence of early
morning erections as reported by the patient."  (Now my opinion, and I cannot
back this up with a study, is that this might be confounded by depression and
other mood disorders. Perhaps depression can suppress morning erections before
an underlying testosterone or nitric oxide issue has developed.)
So what causes morning erections? They seem quite mysterious in many ways
and even "automatic" and "random" at times, i.e. they occur even without an
erotic or sexual dream involved. However, researchers have noted many lines of
evidence and studies that show morning erections are primarily androgen-dependent, i.e. they
are regulated by testosterone and DHT. 
In My Book on Testosterone I point out that several studies have shown that when testosterone
falls far enough, you are likely going to lose and/or greatly diminish the number of
your morning erections. That doesn't necessarily mean that you won't still be
able to "get it up" during the day, however. The reason is that a normal
erection is achieved through a different pathway involving the senses of touch,
sound and sight. However, if you allow your testosterone to remain at low enough
levels for a long enough period of time, you are opening the door
Leakage and other erectile difficulties.
CAUTION: Some men think that DHT (dihydrotesteosterone) doesn't
really matter and just causes hair loss. However, DHT is an incredibly
important androgen and has been shown to be partially responsible for morning
erections.  Before you take any DHT-blocker, be it Saw Palmetto or a drug,
read this link on
Morning erections are not just dependent on DHT and testosterone, however, and the
evidence points to the critical role of nitric oxide as well. Nitric oxide
within the corpus cavernosum, the "erection cavity" within the penis is what
dilates the penile arteries and causes the morning erections.
And that leads to this important question:
"What can one do to get his morning erections back?"
Below we give you few ideas:
1. Testosterone. This may seem obvious, but many men don't make
connection: you have got to have adequate testosterone levels in order to
off those morning erections during REM sleep. One's "morning wood" is
really linked to a different system than standard waking erections and requires
adequate testosterone as a sort of fuel. For example, one study showed
that when levels fall below about 200 ng/dl, men can expect issues. 
verification comes from the fact that several studies show that testosterone
therapy (Hormone Replacement Therapy or HRT) steadily restores nocturnal
erections in men with low testosterone. In fact, one interesting study took a
bunch of hypogonadal men and gave them a hefty shot of testosterone cypionate.
They then monitored the men over the coming weeks during sleep and watched the
morning erections spike and then slowly decrease to about half the frequency.
. The researchers (somewhat cruelly) let the men's testosterone levels
shrink to almost nothing and by the end of 8 weeks, the men's rigidity had gone
from 770 to 590 g, a loss of almost 25%! Yes, these men lost their superpowers
and their nocturnal erections at the same time.
NOTE: It can take time for the restorative process. One study
noted a year of continuous improvement in REM-related erections.  Read this
Venous Leakage to understand how testosterone helps erections via two
primary pathways: 1) increasing eNOS (the "nitric oxide enzyme) activity and 2)
restoring the internal structures and tissues of the penis.
2. Nitric Oxide. Many men notice that when they begin to take one
of the PDE5 Inhibitors (Viagra, Cialis or Levitra), their morning erections
improve. I have also received letters from many men who have noticed the same
thing after taking various
Erectile Supplements - maybe
even an Erectile Supplement Cocktail
increasing their exercise.
The reason, of course, is that all of these usually increase arterial nitric oxide
levels, including those in the penis, and this will in turn help with morning
In fact, improving nitric oxide can have dramatic effects on nocturnal erections
as one Cialis study showed. Cialis has a long half life and its efficacy
is considered to be about 36 hours in most men. One study showed that men
who used 20 mg every other day had dramatically increased morning erections. 
The authors commented that "chronic treatment also produces a dramatic increase
in morning erections, which determines better oxygenation to the penis, thus
providing a rationale for vascular rehabilitation." (The PDE5 Inhibitors like
Cialis also have a log of side effects. See this link on
and Vision Problems for some more information.
A Viagra study using 100 mg nightly for three nights showed some impressive
results as well on men with erectile dysfunction.  The primary change seen
in the case of this PDE Inhibitor were prolonged morning (nocturnal) erections -
in fact, about 60% longer.
Am I advocating taking PDE5 Inhibitors in order to get your morning erections
back? That may be necessary in the short term, but every attempt should be
made to take only the minimal dose necessary. Remember, one can also
PDE5 Inhibitor Resistance and
PDE5 Inhibitor Dependency, so you want
to be careful with these medications. Finally, it is important to rely as
much as possible on
gradual Weight Loss and
boost your nitric oxide and restore you endothelium..
3. Sleep. The importance of sleep to morning erections is often
ignored. Nocturnal erections occur during REM sleep and some men with
erectile struggles report that they seem to be able to achieve nocturnal
erections if they sleep long and thus get that last all-important REM cycle.
4. Sitting. One reader has a novel approach, where he sat slightly
erect, and found that his morning erections re-commenced. See this link on
A Novel Approach to Morning Erections for an example.
5. Pycnogenol. Studies of Prelox, which is just Pycnogenol with a low dose
of L-Arginine, show an increase in morning erections.  Of course, Pycnogenol
is known for improving erectile dysfunction, increase nitric oxide and
decreasing inflammation. See my links on
Pycnogenol and Erectile Strength and The Pros and Cons of Arginine for more
6. Stress. Anecdotally, men have reported to me increased morning
erections after taking any of the cortisol reducers (Vitamin C, S-PS, etc.)
As you know, if you have been looking around the site, I
frequently recommend regular (non-religious) medititation and/or
Muscle Relaxation for the same reason.
The Journal of Sexual Medicine, Nov 2005, 2(6):771–784, "Testosterone and
Sleep-Related Erections: An Overview"
2) The Journal of Clinical Endocrinology & Metabolism, Apr 1 2002,
87(4):1467-1472, "The Effects of Transdermal Dihydrotestosterone in the Aging
Male: A Prospective, Randomized, Double Blind Study"
3) Journal of Sex & Marital Therapy, 1983, 9(1), "Serum testosterone and
prolactin levels in erectile dysfunction"
4) Journal of Sex & Marital Therapy, 1975, 1(4), "The assessment of nocturnal REM
erection in the differential diagnosis of sexual impotence"
5) ARCHIVES OF SEXUAL BEHAVIOR, 1987, 16(2):125-137, "Use of sexual history to
differentiate organic from psychogenic impotence"
6) International Journal of Impotence Research, 2007, 19:200–207, "Relationship
between chronic tadalafil administration and improvement of endothelial function
in men with erectile dysfunction: a pilot study"
7) Journal of Andrology, 18(5):522-527, "Relationship between sleep-related
erections and testosterone levels in men"
8) Journal of Andrology, 13(4):297-304, "A long-term, prospective study of the
physiologic and behavioral effects of hormone replacement in untreated
9) Phytotherapy Research, Mar 2009, 23(3):297-302, "Improvement of seminal
parameters with Prelox®: a randomized, double-blind, placebo-controlled,
9) The Journal of Clinical Endocrinology & Metabolism, Mar 1 1990, 70(3):792-797,
"Testosterone Replacement Therapy and Sleep-Related Erections in Hypogonadal
10) Urology, Dec 2000, 56(6):906-911, "Sildenafil taken at bedtime significantly
increases nocturnal erections: results of a placebo-controlled study"