• Failing to keep adequate notes.
• Prescribing ephedrine to a patient for weight loss despite the patient having hypertension (high blood pressure).
• Prescribing pseudoephedrine in bulk despite submitting to a previous Competence Inquiry that he had stopped doing so.
Dr Twentyman is 30 per cent shareholder in Livingproof and Anti-Ageing New Zealand, a company that trades as High Street Men's Clinic. The central Auckland-based clinic has treated around 9000 patients for conditions such as low libido, erectile dysfunction and premature ejaculation.
The names of the patients involved in the charge against Dr Twentyman have been permanently suppressed.
Dr Twentyman also admits obtaining 19,600 tablets of tamoxifen and improperly dispensing the drug to at least three patients in combination with testosterone.
While Dr Twentyman admits the particulars of the charge against him, he is expected to argue it does not amount to professional misconduct.
The tribunal has the power to suspend Dr Twentyman's registration or cancel it if it finds the charge does amount to professional misconduct.
Twentyman was also a well-known rugby player for Auckland University and Auckland and a flatmate of former All Blacks captain David Kirk.
The hearing is set down for four days.
Dr Twentyman
• High Street Men's Clinic doctor who specialises in treating conditions such as erectile dysfunction, premature ejaculation and low libido.
• Admits 20 particulars of a charge laid by a professional conduct committee relating to the prescription of human growth hormone, anabolic steroids and stimulants.
• Disputes that charge amounts to professional misconduct.
• Faces having registration stripped or suspended.