The participant will be trained to self administer the drug and will be supplied with a PENTHROX commercial inhaler kit .The study nurse will train the participant and supervise its use during the procedure.Immediately following the procedure the participant will be asked to fill out two brief questionnaires. The study nurse will assess the participant for adverse event and will follow-up with a phone call 24 hours later.

Many patients with chronic urological conditions require multiple and sometimes painful urological procedures. Ideally these procedures may be done in the cystoscopy suite without a general anesthetic. Low dose methoxyflurane, (MEOF)is a inhaled, self-administered non-opioid analgesic and has been approved by Health Canada's for the short-term relief of moderate to severe acute pain, associated with trauma or international medical procedures, in conscious adult patients. The brand name is PENTHROX.

This study is a single centre, pilot study to assess the feasibility of using a self-administrated, MEOF for pain relief during minor out-patient urological procedures. Eligible participants will receive a one time dose of the the study medication during a planned, outpatient urological procedure done under cystoscopy in the Cystoscopy clinic

Inclusion Criteria:

1. Conscious adult patients >=

2. Patient is scheduled for cystoscopy And:

   • BOTOX injections for Overactive Bladder /Neuogenic Detrusor Overactivity,
   • Diagnostic hydrodistention for painful bladder syndrome
   • Biopsy or cauterization of bladder tumors
   • Biopsy, cauterization and/or injection of Hunner's lesions
   • Visual urethrotomy/bladder neck incision=/- injection of stricture
   • Evaluation of the complex urinary tract problems

3. Patient (patient/or patient's authorization legal representative) should understand the nature of the study and provide written informed consent

4. Patient is able to follow all study requirements and procedures and complete required questionnaires

Exclusion Criteria:

1. An altered level of consciousness, due to any cause, including head injury, drugs,or alcohol
2. Clinically significant renal impairment
3. Women of child bearing potential who are pregnant or peri partum, including labour
4. A history of liver dysfunction after previous MEOF use or other halogenated anesthetics
5. Hypersensitivity to MEOF or other halogenated anesthetics, or to butylated hydroxytoluene
6. Known or genetically susceptible to malignant hyperthermia or a history of severe adverse reactions in either patient or relatives
7. Exacerbation of an underlying condition (i.e., chronic pain)
8. Clinically evident or potential hemodynamic instability as per the opinion of the investigator
9. Clinically evident respiratory impairment as per the opinion of the investigator
10. Prior treatment with PENTHROX within 3 months

no masking