The pelvic floor is a highly compact area comprised of muscles, tendons, ligaments, fascia, and nerves. Overactive or contracted musculature in the pelvic floor is associated with several conditions such as vulvodynia and urinary incontinence , as well as symptoms such as dyspareunia, pelvic pain, and urinary frequency for which patients seek medical intervention. A number of factors are associated with pelvic floor muscle overactivity including a history of recurrent vulvovaginal infections, prolonged sitting, postural dysfunction, history of traumatic labor and delivery, urogenital cancer, history of physical trauma (such as a fall onto the coccyx or pelvic fracture), anxiety, sexual abuse, and constipation. Overactive pelvic floor (OPF) is understood to be a multifactorial condition requiring a multidisciplinary medical, psychological, and physical therapy team. This chapter will focus on medical therapies for OPF and will summarize the evidence-based data regarding medical interventions available for the treatment of pelvic floor overactivity.

An OPF is related to several possible presentations that physicians are likely to encounter in the clinical setting. Patients describing symptoms of pain, paresthesias, and other sensorimotor pelvic complaints may be suffering from compression of nerves such as the pudendal nerve or any of its branches (dorsal clitoral, perineal, inferior rectal). Other presentations related to OPF include introital dyspareunia, pain with speculum insertion, urinary frequency, the sensation of incomplete emptying with urination, chronic constipation, and rectal fissures. In severe cases, pelvic floor muscle overactivity can cause nonprovoked, chronic vulvovaginal burning and pain (vulvodynia).

Any evaluation of potential OPF should begin with a thorough history. Patients should be questioned about any of the following symptoms: vulvovaginal burning, throbbing, aching, soreness, introital dyspareunia, vaginal dyspareunia, urinary frequency, sensations of incomplete emptying with urinary, constipation, hemorrhoids, rectal fissures, pain with defecation, injury to the sacrum or coccyx, and injury to the lower back or hips. In addition, patients should be asked if they have a history of “holding urine,” aggressive core muscle strengthening exercises, and a history of physical, emotional, or sexual abuse. Affirmative responses to any of these symptoms can be suggestive of OPF.

A brief screening exam can identify the majority of women with OPF and other types of pathologies that are frequently co-morbid with OPF. A description of this exam is as follows: a sensory exam of the vulva is performed using a moistened cotton swab to determine if there are areas that exhibit an abnormal pain response. Women with sexual pain can exhibit allodynia (i.e., the perception of pain upon provocation by a normally nonpainful stimulus such as being touched with a cotton swab) or hyperpathia (i.e., pain provoked by very light touch). This exam should be performed systematically to ensure that all areas of the anogenital region are tested. Initially, the medial thigh, buttocks, and mons pubis are palpated. These areas are typically not painful and this allows the patient to get comfortable with this exam [1]. The labia majora, clitoral prepuce, perineum, and interlabial sulci should then be palpated. Pain in these areas would suggest a process that is affecting the whole anogenital region including vulvar dermatoses, vulvovaginal infections, or neuropathic processes such as pudendal neuralgia. The labia minora are then gently palpated. First, the medial labia minora are gently touched lateral to Hart’s line, which is the lateral boundary of the vulvar vestibule. The cotton swab is then used to gently palpate the vestibule at five locations: at the ostia of the Skene glands (lateral to the urethra), at the ostia of the Bartholin glands (4 and 8 o’clock on the vestibule), and at 6 o’clock at the posterior fourchette. Patients with vestibulodynia experience allodynia with the cotton swab test confined to the tissue of the vulvar vestibule but have normal sensation lateral to Hart’s line. If the pain is localized to the vestibule, it is important to determine if the pain affects the entire vestibule or just the posterior vestibule as pain throughout the entire vestibule is an indication that there is an intrinsic pathology within the mucosa of the vestibular endoderm whereas, pain confined only to the posterior vestibule suggests that the pain is due to OFP [2].

A manual exam is then performed with one finger (instead of the usual two). The examiner’s index finger is inserted through the hymen without touching the vestibule. The finger is firmly pressed downward towards the rectum approximately 2 cm proximal to the hymen. This should elicit the symptom of “pressure” or the “need to defecate” but not pain. Once the patient is normalized to the sensation of pressure, the pelvic muscles are examined. Moderate pressure is applied sequentially to the following muscles: coccygeus, iliococcygeus, pubococcygeus, puborectalis, and obturator internus. When each muscle is palpated, the patient should be asked “is this pressure or discomfort?” In addition, evidence of taught bands, knots, tender points, and trigger points should be noted. Discomfort during this part of the examination is highly suggestive of OFP. Then the urethra and bladder trigone are gently palpated. Intrinsic tenderness of the urethra may be suggestive of a urethral diverticulum or interstitial cystitis, while tenderness of the bladder may be suggestive of either interstitial cystitis or endometriosis.

The ischial spine is then located and the pudendal nerve is palpated as it enters Alcock’s canal. Tenderness of the pudendal nerve is suggestive of pudendal neuralgia. Next, a bimanual examination is performed to assess the uterus and adnexa. Abnormalities in the size, shape, or contour may be indicative of a leiomyoma. A diffusely enlarged, “boggy” and tender uterus may be signs of adenomyosis. Enlargement of the adnexa may represent an ovarian mass, whereas tenderness of the adnexa can often be a sign of a sexually transmitted infection, pelvic inflammatory disease, or endometriosis. A rectovaginal examination is then performed to assess the rectovaginal septum and the posterior cul-de-sac. Thickening or nodularity of the septum, nodularity of the uterosacral ligaments, can be suggestive of endometriosis [1].

If the aforementioned history and physical exam are consistent with a diagnosis of OPF, a referral to a skilled pelvic floor physical therapist is warranted for a more thorough musculoskeletal examination . Medications may be used alone, or as adjuvant treatment in combination with physiotherapy. The authors typically start with diazepam suppositories (Sect. 15.4.2 below) and systemic muscle relaxants such as cyclobenzaprine (Sect. 15.4.3 below) and reserve botulinum toxin type A (BTTA) (Sect. 15.4.1 below) for patients with more recalcitrant OFP. However, there have been no evidence-based algorithms published, therefore, decisions on medications must be made by taking into account each patient’s medical history and concurrent medications.

The following medications have been described for the use of OFP.