Apomorphine

Also known as: apomorphine, apomorphine sublingual, Uprima/Ixense (branded, discontinued)

Sexual Well-Being

In plain English

Apomorphine is a medicine that works through the brain (not directly on blood vessels) to help trigger an erection. A dissolve-in-the-mouth form was studied and marketed for erectile dysfunction but was later discontinued; it is now used in compounded troches. Nausea is the most common side effect. Modern erectile-dysfunction pills are generally preferred.

The science

Apomorphine is a dopamine D1/D2 receptor agonist; centrally, activation in the hypothalamic paraventricular nucleus promotes penile erection via a mechanism independent of the peripheral PDE5 pathway. Randomized trials of sublingual apomorphine (Dula 2000; Heaton) demonstrated significantly higher rates of erections firm enough for intercourse versus placebo, and it was marketed for erectile dysfunction (Uprima/Ixense) before being withdrawn, largely due to limited efficacy relative to PDE5 inhibitors and dose-related nausea. Nausea, dizziness, headache, and rare syncope/hypotension are the main adverse effects. There is no current FDA-approved apomorphine product for erectile dysfunction (apomorphine is FDA-approved for Parkinson 'off' episodes); compounded troches, including combinations with PDE5 inhibitors or oxytocin, are off-label.

References

• Dula et al., Urology 2000 (sublingual apomorphine RCT)
• von Keitz/Heaton et al., BJU Int 2001 (3 mg apomorphine SL crossover RCT)