The purpose of this study is to assess the safety and efficacy of super-concentrated, freeze-dried aloe vera capsules for treatment of interstitial cystitis.

After being informed about the study and potential risks, all participants who have provided written informed consent will be screened to determine eligibility for study entry. Participants who meet the eligibility requirements will be randomized in a double-blind manner (participant and investigator) in a 4:1 ratio to aloe vera (study group) or placebo (control group), respectively. The dosing regimen will be increased by 3 capsules every month for 3 months and then reduced by 2 capsules every week during the fourth month for both groups. Participants will remain in the study for sixteen weeks.

Inclusion Criteria:

• Females or males, aged 18 years or older
• Females of childbearing potential must agree to use acceptable methods of birth control. Acceptable methods are oral and injectable preparations, double barrier, vasectomized partner, or abstinence.
• Participant must sign and date the informed consent.
• Participant must report a urinary frequency of at least 11 times per 24-hour day, on average over the previous four weeks.
• Participant must report a pain/discomfort score of 4 or greater on a 0-9 Likert scale.
• These reported urinary symptoms of frequency and pain/discomfort must have been present for at least the previous 24 weeks prior to the first baseline screening visit.
• Participants must report in the baseline voiding diary at least one voided volume greater than or equal to 75cc in a 24-hour period.

Exclusion Criteria:

• Known allergy or intolerance to aloe vera in any form as reported by the participant or derived from medical records.
• History of Bladder tumors (malignant or benign).
• Current active bladder or urethral calculus.
• History of urethral cancer within the previous five years.
• Any disease which, in the opinion of the investigator, may be unstable or have bearing on the outcome of the study, including severe debilitating concurrent medical conditions such as coronary artery disease, azotemia, moderate to severe hepatic insufficiency, etc.
• Previous treatment with Cytoxan (cyclophosphamide).
• History of cyclophosphamide or chemical cystitis or tuberculosis or radiation cystitis.
• History of pelvic radiation treatment, bladder cancer or cancer in situ, or urethral cancer.
• History of any other neoplastic process currently requiring systemic, nonprophylactic treatment.
• History of urethral diverticulum.
• Inability to void spontaneously.
• Subjects with interstitial cystitis symptoms alleviated by current therapy regimen.
• Uncontrolled diabetes mellitus.
• Previous enrollment in an aloe vera study.
• Previous use of Desert Harvest super-concentrated, freeze-dried aloe vera capsules.
• Any imminent change in residence that could compromise compliance.
• Unlikely to be compliant due to unmanaged medical or psychological problem, including dementia, aphasia, or other deficits of cognition or speech/language function that will interfere with the participant's ability to complete the study.
• Substance abuse or dependency problem within the past two years for which patient received no treatment.

Male-Specific Exclusion Criteria:

• Males with a history of prostate cancer within the previous five years.
• Males with a prostatic infection within the previous three months.

Female-Specific Exclusion Criteria:

• Females with a history of uterine, cervical, or vaginal cancer within the previous five years.
• Pregnant or lactating females.