Sexual Health Supplement Leads to Priapism

SOURCE: Campanelli M, et al. Int J Impot Res 2015;28:39-40.

Were you to plug “Tribulus terrestris supplement” into Google, numerous opportunities to purchase OTC supplements, within a wide range of affordability, would appear. It appears tribulus has some effects similar to PDE5 inhibitors (e.g., sildenafil) that would potentially enhance sexual function in males: enhancement of nitric oxide production in the endothelium of the corpora cavernosa, and cavernosal smooth muscle relaxation. Apparently, tribulus — also known as puncture vine or Gokhru — grows well in numerous countries around the world (especially China, India, the southern United States, and Spain), and has long been utilized by herbalists as a primary or contributing ingredient in herbal supplements.

Since OTC supplements lack FDA oversight and regulation, it should not be surprising that unanticipated adversities occur. Such misadventure may be attributed to mislabeled amounts of constituents, adulterants, idiosyncratic reactions, or may represent spontaneous events unrelated to ingestion of the supplements.

Campanelli et al reported a case of a young man with persistent priapism (duration = 72 hours) subsequent to 2 weeks of daily Tribulus terrestris supplementation. Invasive treatment (aspiration of corpus cavernosa and creation of a cavernoglandular shunt) was required for resolution, with restoration to nearly complete pre-morbid sexual function at 8 months follow-up. This is not the first reported case of Tribulus terrestris associated with priapism. In addition to personal preferences, which often motivate patients to seek non-traditional treatments, the current high cost of FDA-approved pharmacologic treatments may motivate some individuals to seek much less expensive OTC remedies. If clinicians become aware of patient tribulus use, they should caution users about the potential for priapism and encourage patients to seek prompt consultation if a prolonged erection occurs.


Eluxadoline for IBS-D

SOURCE: Lembo AJ, et al. N Engl J Med 2016;374:242-253.

The burden of suffering sustained by persons with diarrhea-predominant irritable bowel syndrome (IBS-D) is substantial, and clinicians often underestimate the condition. While OTC remedies (e.g., loperamide, fiber) may provide some relief for IBS-D, residual symptoms continue to plague most patients.

Eluxadoline is a recently FDA-approved pharmacologic treatment for IBS-D. Mu-receptors are prominently active in the GI system, as evidenced by the commonplace development and persistence of constipation in patients using opioid analgesics. The primary mechanism of eluxadoline is peripheral (i.e., not in the CNS) mu-receptor mediated reduction in colonic visceral hypersensitivity. At the same time, an additional mechanism of eluxadoline — delta-receptor antagonism — appears to reduce the degree of constipation typically induced by pure mu-receptor agonists.

Lembo et al reported results from placebo-controlled trials of eluxadoline in IBS-D (n = 2427). The primary outcome was the number of patients who experienced decreased abdominal pain as well as improved stool consistency for at least half the days throughout the studies (one study lasted 12 weeks, the other lasted 26 weeks). Eluxadoline demonstrated a modest but statistically significant greater ability to reach the primary endpoint and was generally well tolerated. Cases of pancreatitis occurred during eluxadoline treatment, but not during placebo treatment. Because these cases occurred in post-cholecystectomy patients or in persons who used excessive alcohol, until more information is available, clinicians would be wise to avoid eluxadoline in these populations.


New Orthostatic Hypotension Category

SOURCE: Gorelik O, Cohen N. J Am Soc Hypertens 2015;9:985-992.

Traditionally, orthostatic hypotension (OH) is defined as a drop in systolic blood pressure > 20 mmHg or diastolic blood pressure > 10 mmHg (or both) within 3 minutes of standing from a supine position. The consequences of OH include adverse symptoms, such as dizziness or “coat-hanger” headache, as well as serious or even fatal events consequent to falls. Studies on OH measured when patients transfer from supine to the seated position are infrequent; Gorelik and Cohen reviewed data from 17 different studies to elucidate the literature on seated postural hypotension (SOH).

Similar to OH, the prevalence of SOH increases with age and is more frequent among patients ingesting antihypertensive medications. Probably because of the lack of a firmly established definition of SOH, measurement methods varied among studies, such that changes in blood pressure were measured within as little as 1 minute to as long as 5 minutes or even longer after changing from the supine to seated posture; most data employed the standard blood pressure change (> 20/10 mmHg) to define SOH. Symptoms evoked among patients with SOH were essentially the same as those observed in patients with “typical” OH. Some experts have advised routinely measuring orthostatic blood pressure in patients with underlying neurologic disorders, such as Parkinson’s disease, in which OH prevalence is distinctly higher. Measurement of postural changes in blood pressure from supine to seated may be helpful to sort out symptoms such as dizziness or falls, especially in older patients.