Erectile Dysfunction — NZ Condition Guide | KiwiMeds

What is Erectile Dysfunction?

Erectile dysfunction (ED) is the persistent inability to achieve or maintain an erection sufficient for sexual activity. It is more common than many people realise — affecting up to 40% of men over 40 and increasing with age. ED is not just a sexual problem — it is often a marker of underlying cardiovascular or metabolic disease and can have a significant impact on mental health and relationships.

Overview

ED can have physical causes (reduced blood flow, nerve damage, hormonal issues), psychological causes (anxiety, depression, stress, relationship issues), or — most commonly — a combination of both. Physical risk factors include cardiovascular disease, diabetes, high blood pressure, obesity, smoking, excessive alcohol, sleep apnoea, and certain medications (some antihypertensives, antidepressants). ED is often an early warning sign of cardiovascular disease — men with ED have twice the risk of a heart attack or stroke.

Treatment in New Zealand

Treatment depends on the cause. Lifestyle changes are important — losing weight, exercising, quitting smoking, reducing alcohol. PDE5 inhibitors (sildenafil/Viagra, tadalafil/Cialis, vardenafil) are the most commonly prescribed medications and are effective in up to 70% of men. They require sexual stimulation to work. Sildenafil is available without prescription from NZ pharmacies since 2019 but is not Pharmac-funded. Tadalafil is Pharmac-funded for men with certain conditions. Psychological therapy (sex therapy, CBT) helps when psychological factors are significant.

NZ-Specific Information

Sildenafil (Viagra) is available over the counter from NZ pharmacies for men over 35 who have consulted with the pharmacist — it is not funded by Pharmac. If you have heart disease or take nitrate medications (GTN spray, isosorbide mononitrate), you must not take PDE5 inhibitors — this combination can cause a dangerous drop in blood pressure. Always consult a healthcare professional before starting treatment.

Frequently Asked Questions

Is ED normal with age? ED becomes more common with age but is not inevitable. It deserves investigation as it may indicate cardiovascular disease. Is ED curable? In many cases, addressing the underlying cause (weight loss, stopping smoking, treating diabetes or hypertension) significantly improves ED. Are ED medications safe? Generally yes, but not if you take nitrates for heart disease. Consult your doctor or pharmacist.

Supplements That May Support Management

⚠️ Important: The supplements listed below have varying levels of clinical evidence. They are not a substitute for prescribed medications and should only be considered as adjunctive support under the guidance of a qualified healthcare professional. Always inform your GP or pharmacist before commencing any supplement, as interactions with prescribed medicines are possible.

• L-Arginine — L-Arginine is a precursor to nitric oxide, which mediates penile vascular smooth muscle relaxation central to erection. Supplementation at 3–5 g/day has demonstrated improvements in erectile function scores in men with mild-to-moderate ED, with additive benefit when combined with phosphodiesterase-5 inhibitors.
• L-Citrulline — L-Citrulline is converted to L-arginine in the kidneys more efficiently than direct arginine supplementation. At 1.5–3 g/day, it provides sustained increases in nitric oxide bioavailability and has demonstrated improvements in erection hardness scores in a randomised trial.
• Panax Ginseng (Korean Red Ginseng) — Korean red ginseng (Panax ginseng) has the most consistent evidence base among herbal supplements for erectile dysfunction, with multiple trials demonstrating improvements in erectile function scores. Proposed mechanisms include nitric oxide synthase stimulation.
• Vitamin D — Vitamin D deficiency is associated with increased ED risk, likely via endothelial dysfunction and reduced testosterone production. Supplementation is recommended where deficiency is confirmed.
• Zinc — Zinc is essential for testosterone biosynthesis. Deficiency is associated with hypogonadism and reduced libido. Supplementation at 25–45 mg/day may improve testosterone levels in deficient men.

Relevant Vaccinations

Individuals living with erectile dysfunction may benefit from the following vaccinations. Please discuss your vaccination status with your GP or practice nurse, as eligibility and funding through the New Zealand National Immunisation Schedule may apply.

• Influenza (annual) — General preventive health recommendation. Maintaining cardiovascular health — the primary underlying cause of erectile dysfunction — is supported by reducing infection-related inflammatory burden.
• COVID-19 — COVID-19 has been associated with erectile dysfunction via endothelial dysfunction, vascular inflammation, and testosterone reduction in some studies. Maintaining vaccination may reduce these risks.
• HPV — HPV vaccination is recommended for eligible males and females. HPV can cause penile and anal cancers as well as genital warts.

Dietary Guidance

Evidence-based dietary modifications play a meaningful role in the management of erectile dysfunction. The following foods are generally recommended as part of a balanced, condition-appropriate diet. A referral to a registered dietitian may be beneficial for personalised nutritional planning.

• Mediterranean dietary pattern — Strong evidence links Mediterranean dietary adherence with reduced ED incidence and severity, primarily through improvements in endothelial function, cardiovascular health, and testosterone levels.
• Watermelon — Rich in L-citrulline, a nitric oxide precursor. Regular consumption may provide mild vasodilatory benefit relevant to erectile function.
• Dark chocolate (≥70% cacao) — Flavanols stimulate nitric oxide production and improve vascular endothelial function.
• Oily fish, nuts, olive oil — Support vascular health and testosterone metabolism through anti-inflammatory effects and essential fatty acid provision.
• Limit: alcohol, ultra-processed foods — Chronic alcohol use impairs testosterone production and vascular function. Ultra-processed dietary patterns are associated with significantly increased ED risk through adiposity, insulin resistance, and endothelial dysfunction.

Related Conditions & Medications

Related conditions: Type 2 Diabetes, Hypertension.