Diltiazem and Internal Anal Sphincter

Topical Nifedipine With Lidocaine Ointment vs. Active Control for Treatment of Chronic Anal Fissure

“…The effects of nifedipine and other calcium channel antagonists in producing a reduction of resting tone and an attenuation of agonist-induced contractions in the internal anal sphincter smooth muscle have been assessed. [33][34][35][36] Nifedipine and diltiazem showed efficacy in reducing anal resting pressure and in healing chronic anal fissure after oral administration. Side effects of nifedipine and diltiazem after oral administration include facial flushing, mild headaches, and postural hypotension.…”

Comparison of Observational and Controlled Clinical Trials of Diltiazem in the Treatment of Chronic Anal Fissure

“…Clinical trials show that healing can be achieved in 45-80% patients with GTN therapy, but significant adverse effects such as headache, tachyphylaxis and occasional loss of flatus control have also been reported. Some studies report poor long-term outcome of GTN therapy; only 6% of patients healed in 12 months [10,[20][21][22][23]. Recently, diltiazem has been found efficacious in the treatment of chronic anal fissure.…”

“…Besides this, chronic anal fissure patients usually have high rectal pressure and sphincter hypertonia, which can compromise local blood flow. Treatment with diltiazem relaxes the sphincter and enhances the local blood flow clearly by different pathways [10,23].…”

Progress in the understanding and treatment of chronic anal fissure

“…The proctalgia immediately recurred when the diltiazem was discontinued during warmer weather. Diltiazem 60 mg orally51 52 and 2% gel topically52 have been shown to reduce the MRAP by 21% and 28% respectively in healthy volunteers. Whereas oral diltiazem caused postural dizziness in 20% of cases, topical diltiazem caused no side effects 52…”