Impotence (Erectile dysfunction [ED])

Japanese: インポテンツ（ED）（英語表記）Impotence (Erectile dysfunction [ED])

What is the disease?

Enough to have sex erection ( Erection ) This refers to a condition in which a man is unable to have sexual intercourse because he is unable to get or maintain an erection. Recently, it has been called ED (Erectile Dysfunction). Intravaginal ejaculation disorder is when a man is unable to ejaculate inside the vagina, even though he is able to get an erection and have sexual intercourse, and is considered a subtype of impotence. It is estimated that there are approximately 5 million patients in Japan.

What is the cause?

Impotence is classified as primary impotence, where a man is born never able to have an erection, and secondary impotence, where a man was able to have an erection for a time but later became impotent.

Primary puberty is seen in people who do not have secondary sexual characteristics due to hypopituitarism, etc. In contrast, secondary puberty is seen in people aged 20 to 40 years old, and is often associated with mental and physical problems such as newlywed impotence. Psychogenic ( New life ) It is known that in people over 40, the cause is organic, that is, damage to the nerves and blood vessels related to erectile dysfunction caused by aging, chronic diseases (diabetes, heart disease, arteriosclerosis, depression), trauma to the pelvis, bladder, prostate, or rectum, or surgery.

In addition, the head Spinal cord ( Spinal cord ) Impotence can also be caused by illness or trauma. In addition, taking antihypertensive drugs, antidepressants, and antiandrogens can also cause impotence.

How symptoms manifest

At first, you may only experience occasional erectile dysfunction, but if the condition becomes severe, it may become a constant condition.

Testing and diagnosis

The patient will be asked about the presence or absence of erection during sexual activity in the past four weeks, its hardness, whether it was possible to insert, and whether it was possible to maintain it. The presence or absence, frequency, and hardness of early morning erections are also useful for diagnosis. In general, if early morning erections are common, it is considered to be psychological or psychogenic impotence.

Honeymoon impotence is often seen during the honeymoon, but masturbation is still possible and early morning erections also occur.

In addition, the appearance or absence of secondary sexual characteristics, e.g. penis ( Inquiry ) Blood tests, including those for testicular size and male hormones, are required. It is also necessary to check for chronic diseases such as diabetes.

In addition, we will check the patient's history of drinking, smoking, depression, etc., and history of taking antihypertensive medications.

A special method is called RigiScan, which is a method to check whether erections occur during sleep. If erections occur during the night, psychogenic impotence is suspected. There are also tests that measure blood flow to the penis with ultrasound and inject drugs into the penis to induce erection.

Treatment methods

For primary impotence, male hormone replacement therapy is used to bring about secondary sexual characteristics. For mental or psychogenic impotence, such as newlywed impotence or dysejaculatory dysfunction, behavioral therapy and psychotherapy are used. If this is ineffective, sildenafil citrate (Viagra), vardenafil hydrochloride hydrate (Levitra), tadalafil (Cialis), etc. may be used.

In organic impotence, the underlying disease (diabetes, depression, etc.) that is causing it must be treated. It is also recommended to discontinue medications that may cause impotence. However, these are often ineffective, and Viagra and other medications are often used. However, before administering Viagra or other medications, it is necessary to check that the patient does not have any complications such as heart disease and is not taking nitrates (nitroglycerin, etc.).

Other than ED medication, there are other methods such as penile Smooth muscle relaxants ( Safe and secure ) For example, there are intracavernous self-injection methods in which prostaglandins or papaverine hydrochloride are self-injected, vacuum erection aids are used, and aids are surgically inserted into the penis.

What to do if you notice an illness

If you wish to receive psychotherapy or behavioral therapy, please see a specialist urologist or psychiatrist.

Those who wish to take Viagra or similar drugs should visit an internal medicine or urology department, and if there are no abnormalities in blood tests or electrocardiograms, they will be prescribed. If ED drugs are ineffective, it is necessary to visit a urology department. Since this is a special treatment, please inquire in advance whether it is possible to receive treatment.

Kazuo Saito

Source: Houken “Sixth Edition Family Medicine Encyclopedia” Information about the Sixth Edition Family Medicine Encyclopedia

Japanese:

どんな病気か

　性交渉をするための十分な勃起(ぼっき)が得られない場合や、勃起を維持できないために性交ができない状態を指します。最近ではED（Erectile Dysfunction）と呼ばれています。腟内射精障害は、勃起が得られ性交ができるにもかかわらず、腟内では射精できないもので、インポテンツの亜型と考えられています。日本では約500万人の患者さんがいると推測されています。

原因は何か

　生まれつき、まったく勃起したことがない一次性のインポテンツと、一時的には可能であったがその後インポテンツになった二次性のインポテンツに分類されます。

　一次性は、下垂体機能低下症などにより二次性徴が発現していない人にみられます。これに対し二次性のものは、20～40歳では新婚インポテンツなどの精神、心因性(しんいんせい)のものが多いことが知られています。40歳以上では器質性、つまり加齢、慢性疾患（糖尿病、心臓病、動脈硬化、うつ病）、骨盤・膀胱や前立腺、直腸の外傷、手術などにより、勃起に関係する神経や血管が損なわれたことが原因です。

　また、頭部・脊髄(せきずい)の病気や外傷によってもインポテンツになることがあります。そのほか、降圧剤、抗うつ薬、抗アンドロゲン薬を服用するとインポテンツになることがあります。

症状の現れ方

　初めは時々勃起しなくなるだけですが、重症になると常時このような状態になります。

検査と診断

　過去4週間の性的行為での勃起の有無、硬度、挿入可能であったかどうか、維持可能であったかどうかについて問診します。早朝勃起の有無や頻度、その時の硬度も診断に有用です。一般に早朝勃起が普通にあれば、精神・心因性のインポテンツと考えられます。

　新婚インポテンツは新婚旅行時などで見かけられますが、マスターベーションは可能で早朝勃起現象もあります。

　そのほか、二次性徴の出現の有無、たとえば陰茎(いんけい)や精巣の大きさや男性ホルモンを含めた血液検査が必要になります。また、糖尿病などの慢性疾患がないかどうかのチェックも必要です。

　さらに、飲酒歴、喫煙、うつ病などの有無、降圧薬などの内服歴を調べます。

　特殊なものとしては、リジスキャンといって、睡眠中に勃起現象が起こっているかどうかを検査する方法があります。夜間に勃起しているようならば、心因性のインポテンツが疑われます。また、超音波で陰茎の血流を測定することや、陰茎に薬を注入して勃起を誘発する試験もあります。

治療の方法

　一次性のインポテンツでは、二次性徴を発現させるために男性ホルモンなどの補充療法を行います。新婚インポテンツや腟内射精困難症などの精神・心因性のインポテンツでは、行動療法、心理療法があります。これで効果がなければクエン酸シルデナフィル（バイアグラ）、塩酸バルデナフィル水和物（レビトラ）、タダラフィル（シアリス）などを用いることになります。

　器質性のインポテンツでは、その原因になっている基礎疾患（糖尿病、うつ病など）の治療が必要です。また、インポテンツを起こす可能性のある薬を中止することがすすめられます。しかし、効果のみられないことも多く、バイアグラなどがよく使われています。ただし、バイアグラなどの投与前に、心疾患などの合併症がないこと、硝酸剤（ニトログリセリンなど）を服用していないことを確認する必要があります。

　ED治療薬以外の方法としては、陰茎に平滑筋弛緩薬(へいかつきんしかんやく)たとえばプロスタグランジンや塩酸パパベリンを自己注射する陰茎海綿体内自己注射法、陰圧式勃起補助具を使う方法、陰茎内に手術的に補助具を挿入する方法があります。