Editing CUA: Interstitial Cystitis (2016) (section)

=== Second-line: medications (oral, intravesical) ===

==== Oral (7): ====
# '''<span style="color:#ff0000">Amitriptyline</span>''' 25–75 mg po qhs
# '''<span style="color:#ff0000">Cimetidine</span>''' 400 mg po bid
# '''<span style="color:#ff0000">Hydroxyzine</span>''' 10–50 mg po qhs (perhaps in patients with an allergy history)
# '''<span style="color:#ff0000">Pentosan polysulfate</span>''' 100 mg po tid '''(PPS, Elmiron)'''
#* '''Expected benefits are predicted to be marginal'''
#* Common side effects included: diarrhea (25%); headache (18.2%); nausea (15%); pelvic pain (13%); abdominal pain (13%); and alopecia (5%).
# '''Gabapentinoids'''
#* Option in patients with neuropathic pain
# '''Quercetin'''
# '''Cyclosporine A'''
#* Close patient monitoring, including blood pressure, Cr and CyA levels are necessary. '''Due to the potential for serious side effects, should be reserved for severe patients with inflammation refractory to other treatment options.'''

==== Intravesical ====
* '''<span style="color:#ff0000">Recommended (3): DMSO, heparin, lidocaine'''
*# '''<span style="color:#ff0000">Dimethylsulfoxide (DMSO)'''
*#* '''<span style="color:#ff0000">MOA: organic solvent with anti-inflammatory and analgesic properties'''
*#* Administered as a 50 mL solution of 50% DMSO with a dwell time of 30‒60 minutes, once weekly for 6 weeks. Monthly maintenance doses may be considered.
*#* Overall, favourable safety profile. Typical side effects include halitosis (garlic-like breath, as it is eliminated through the lungs) and potential flare-up after the first instillation, which usually improves after the second one.
*#* Theoretically may cause dissolution of collagen that could '''potentially cause bladder fibrosis if used on a long-term basis.'''
*# '''<span style="color:#ff0000">Heparin (alone or in combination)'''
*#* '''<span style="color:#ff0000">MOA: GAG analogue'''
*#* May be instilled intravesically with '''virtually no systemic absorption'''
*#* '''DMSO combined with heparin better than DMSO alone''' (further reduces and defers relapses)
*# '''<span style="color:#ff0000">Lidocaine'''
*#* '''<span style="color:#ff0000">MOA: local anesthetic'''
*#* Instillation on a daily or weekly basis of alkalinized lidocaine
*#* '''Option for short-term relief IC/BPS symptoms''', primarily bladder pain
* '''Options (hyaluronic acid, chondroitin sulfate, pentosan polysulfate, oxybutynin)''':
*# '''Hyaluronic acid'''
*#* MOA: May help replenish the GAG layer of the bladder.
*#* Efficacy unknown; 3 negative trials have been completed without published results
*# '''Chondroitin sulfate'''
*#* MOA: May help replenish the GAG layer of the bladder.
*#* Should not be used as monotherapy, but may be considered as part of multimodal therapy for IC/BPS.
*# '''Pentosan polysulfate (PPS, Elmiron)'''
*#* MOA: a weak analogue of heparin, may replenish the deficient GAG layer
*#* '''Intravesical PPS may be more effective than oral''' since only 1‒3% of oral PPS reaches the bladder.
*#* '''May be used alone or in combination with oral PPS'''
*# '''Oxybutynin'''
* '''Not recommended (resiniferatoxin, BCG):'''
*# Resiniferatoxin (RTX)
*#* A potent analogue of the chili pepper extract capsaicin; a neurotoxin that desensitizes C-fiber afferent neurons that transmit pain and, thus, could alleviate pain in IC/BPS.
*#* Based on conflicting Level 2 evidence and the adverse side effect profile, RTX is not recommended
*# Bacillus Calmette-Guerin (BCG)