Other Gastrointestinal Drugs

The altered composition of bile increases the capacity for cholesterol uptake. Thus, gallstones can be dissolved in the course of a 1- to 2 y treatment, provided that cholesterol stones are pure and not too large ( 15 mm), gall bladder function is normal, liver disease is absent, and patients are of normal body weight. UCDA is more effective (daily dose, 8-10 mg) and better tolerated than is CDCA (15 mg/d frequent diarrhea, elevation of liver enzymes in plasma). Stone formation may recur after cessation of successful therapy. 

Compared with surgical treatment, drug therapy plays a subordinate role. 

UCDA may also be useful in primary biliary cirrhosis. 

Choleretics are supposed to stimulate production and secretion of dilute bile fluid. This principle has little therapeutic significance. 

Cholekinetics stimulate the gallbladder to contract and empty, e.g., egg yolk the osmotic laxative MgS04, the cholecystokinin-related ceniletide (given parenterally). Cholekinetics are employed to test gallbladder function for diagnostic purposes. 

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Plasma digoxin levels may decrease when the drug is administered with bleomycin. When bleomycin is used witii cisplatin, there is an increased risk of bleomycin toxicity Pulmonary toxicity may occur when bleomycin is administered with other antineoplastic drugs. Plicamycin, mitomycin, mitoxantrone, and dactino-mycin have an additive bone marrow depressant effect when administered with other antineoplastic drugs. In addition, mitomycin, mitoxantrone, and dactinomycin decrease antibody response to live virus vaccines. Dactinomycin potentiates or reactivates skin or gastrointestinal reactions of radiation therapy There is an increased risk of bleeding when plicamycin is administered witii aspirin, warfarin, heparin, and the NSAIDs. 

SSRIs are the drugs of choice for PD. All SSRIs have demonstrated effectiveness in controlled trials, with 60% to 80% of patients achieving a panic-free state.28,48,49 With similar efficacy reported and no trials comparing SSRIs with other SSRIs, selection generally is based on pharmacokinetics, drug interactions, side effects, and cost differences (see Chap. 35 for more discussion). The most common side effects of SSRIs include headaches, irritability, nausea and other gastrointestinal complaints, insomnia, sexual dysfunction, increased anxiety, drowsiness, and tremor.49 SSRIs should not be discontinued abruptly to avoid a withdrawal syndrome characterized by dysphoric mood, irritability, and agitation. 

Bonviva consists of ibandronic acid, a bisphosphonate and is available as 150 mg tablets and 1 mg/mL injection. Patients receiving the oral formulation for the treatment of postmenopausal osteoporosis are advised to take one tablet once a month. Absorption of bisphosphonates from the gastrointestinal tract may be effected by food or other administered drugs. Therefore patients are advised to take the Bonviva 150 mg tablet at least 1 hour before breakfast or another oral medicine and to continue standing or sitting upright for at least 1 hour after administration. 

Additional nucleoside analogues like the purine dideoxynucleosides lamivudine (3TC) and dideoxy-cytidine (ddC, zalcitabine) act in the same way as AZT. Resistance against these agents may show different patterns. They are generally less toxic than AZT. Adverse effects include diarrhoea and other gastrointestinal disturbances, headache, anxiety, restlessness and insomnia. Also hepatotoxicity can occur, probably because some of these drugs might have also some affinity for human DNA polymerases in the liver. 

Principal side effects are gastrointestinal and central nervous system symptoms, including drowsiness, dizziness, and diarrhea. Zolpidem may increase the depressant effects of other sedative drugs, such as the an-tipsychotics, tricyclic antidepressants, and antihistamines. 

As might be expected, ganglionic blockers produce a multitude of side effects because of the inhibition of both sympathetic and parasympathetic responses. Some adverse effects include gastrointestinal discomfort (nausea, constipation), urinary retention, visual disturbances, and orthostatic hypotension. At higher doses, they may even exhibit some neuromuscular blocking activity. These and other side effects may be quite severe in some patients. Fortunately, ganglionic blockers are usually not used for extended periods because the patient is placed on other antihypertensive drugs when the hypertensive crisis is resolved. 

Many oncologists co-prescribe ranitidine and dexamethasone due to the gastric irritant effect of corticosteroids which can lead to dyspepsia, particularly if a patient is also concurrently receiving other gastrointestinal irritants such as non-steroidal anti-inflammatory drugs (NSAIDs). 

Gastrointestinal adverse effects are one of the major disadvantages of SSRIs. The most common is nausea, and the incidence is said to be 20% or more for paroxetine (45,46), sertraline (47), fluvoxamine (5), fluoxetine (48), and citalopram (10,49). Although nausea can lead to drug withdrawal, it usually disappears after a few weeks. Other gastrointestinal symptoms that occur commonly with fluoxetine and sertraline are loose stools and diarrhea (47,48,50), while constipation has been more often reported with fluvoxamine (5) and paroxetine (45,46). 

By reducing gastrointestinal motility, neuroleptic drugs increase the systemic availability of digoxin and other inotropic drugs and thereby increase the potential for toxicity (624). 

Moderately toxic by subcutaneous route. Human systemic effects by ingestion dyspnea, nausea, other gastrointestinal effects. Experimental reproductive effects. Mutation data reported. A strong irritant due to its oxidizing properties. Used in production of drugs of abuse, as a topical antibacterial agent, and a chemical reagent. 

Gastrointestinal adverse effects are more common with halofantrine than with other antimalarial drugs (11). 

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