Calcium channel blockers constipation with

Other agents are also used for the treatment of manic-depressive disorders based on preliminary clinical results (177). The antiepileptic carbamazepine [298-46-4] has been reported in some clinical studies to be therapeutically beneficial in mild-to-moderate manic depression. Carbamazepine treatment is used especially in bipolar patients intolerant to lithium or nonresponders. A majority of Hthium-resistant, rapidly cycling manic-depressive patients were reported in one study to improve on carbamazepine (178). Carbamazepine blocks noradrenaline reuptake and inhibits noradrenaline exocytosis. The main adverse events are those found commonly with antiepileptics, ie, vigilance problems, nystagmus, ataxia, and anemia, in addition to nausea, diarrhea, or constipation. Carbamazepine can be used in combination with lithium. Several clinical studies report that the calcium channel blocker verapamil [52-53-9] registered for angina pectoris and supraventricular arrhythmias, may also be effective in the treatment of acute mania. Its use as a mood stabilizer may be unrelated to its calcium-blocking properties. Verapamil also decreases the activity of several neurotransmitters. Severe manic depression is often treated with antipsychotics or benzodiazepine anxiolytics. 

Constipation may be caused by slow intestinal transition, pelvic floor dysfunction, bowel dysfunction like irritable Bowel syndrome and tumours, but can also be secondary to other diseases and life conditions. Many medicines cause constipation, for example opiates, calcium channel blockers and drugs with anticholinergic effects, e.g. antidepressants. 

CALCIUM CHANNEL BLOCKERS IMATINIB t plasma concentrations of imatinib when is co-administered with dilti-azem, nifedipine or verapamil, t risk of toxicity (e.g. abdominal pain, constipation and dyspnoea) and of neurotoxicity (e.g. taste disturbances, dizziness, headache, paraesthesias and peripheral neuropathy) Due to inhibition of hepatic metabolism of imatinib by the CYP3A4 isoenzymes by diltiazem Monitor for clinical efficacy and for the signs of toxicity listed along with convulsions, confusion and signs of oedema (including pulmonary oedema). Monitor electrolytes and liver function, and for cardiotoxicity... 

Throbbing headache, facial warmth and flushing, and dizziness are minor complaints associated with the use of calcium channel blockers these effects are beheved to be caused by inhibitory actions on smooth muscle (20). Palpitation, muscle cramps, and pedal edema also occur (21-27). Dizziness, facial flushing, leg edema, postural hypotension, and constipation have been reported in up to one-third of patients. They are rarely severe and often abate on continued therapy. More serious adverse effects, mainly those affecting cardiac conduction, are much less common, and only rarely is withdrawal necessary. 

Because of effects on smooth muscle, the calcium channel blockers (particularly verapamil (96) but also diltiazem) can cause constipation. This may be due to colonic motor activity inhibition (97). Gastroesophageal reflux can also occur, and the calcium channel blockers should be avoided in patients with symptoms suggestive of reflux esophagitis (98). Calcium channel blockers (verapamil, diltiazem, and nifedipine) can also be associated with an increased incidence of gastrointestinal bleeding, as reported in a prospective cohort study in 1636 older hypertensives, with a relative risk of 1.86 (95% Cl = 1.22, 2.82) compared with beta-blockers (7). However, this finding was not confirmed in other retrospective studies (13,99,100). 

Most side effects of the calcium channel blockers are related to their mechanism of action. Verapamil and diltiazem can both cause sinus bradycardia and may worsen CHF. Constipation has been associated with verapamil use. The dihydropyridines often cause symptoms associated with vasodilatation, such as facial flushing, peripheral edema, hypotension, and headache. Because dihydropyridines are potent vasodilators, they can cause reflex tachycardia, which may precipitate palpitations, worsening angina, or Ml. Lastly, all calcium channel blockers can cause Gl complaints and fatigue. 

A 25-year-old woman with a history of migraine headaches was started on a calcium channel blocker 6 months ago for prophylaxis therapy. She now reveals that she has been having problems with constipation since starting therapy. In addition, she says that her gums are "overgrowing." PMH Depression and diabetes. Which calcium channel blocker is the most likely cause of her side effects ... 

The calcium channel blockers generally are considered seconder third-line options for preventive treatment when other drugs with established clinical benefit are ineffective or contraindicated. Verapamil is the most widely used calcium chaimel blocker for preventive treatment, but it provided only modest benefit in decreasing the frequency of attacks in two placebo-controlled studies." The therapeutic effect of verapamil may not be noted for up to 8 weeks after initiation of therapy. Side effects of verapamil may include constipation, hypotension, bradycardia, atrioventricular block, and exacerbation of congestive heart failure. Evaluations of nifedipine, nimodipine, diltiazem, and nicardipine have yielded equivocal results. ... 

E. Toxicity The calcium channel blockers cause constipation, edema, nausea, flushing, and dizziness. More serious adverse effects include congestive heart failure, atrioventricular blockade, and sinus node depression these are more common with verapamil than with the dihydropyridines. Bepridil may induce torsade de pointes and other arrhythmias. 

Monitoring for major adverse effects should be undertaken they include headache and dizziness with nitrates fatigue and lassitude with /J-blockers and peripheral edema, constipation, and dizziness with calcium channel antagonists. 

Verapamil (Table 1), the first slow channel calcium blocker synthesized to selectively inhibit the transmembrane influx of calcium ions into cells, lowers blood pressure in hypertensive patients having good organ perfusion particularly with increased renal blood flow. Sustained-release verapamil for once a day dosing is available for the treatment of hypertension. Constipation is a prominent side effect. Headache, dizziness, and edema are frequent and verapamil can sometimes cause AV conduction disturbances and AV block. Verapamil should not be used in combination with -adrenoceptor blockers because of the synergistic negative effects on heart rate and contractile force. 

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