Amitriptyline retention

Table 1 gives the tailing factor for the basic analyte amitriptyline at neutral pH on several commercially available packings. One can clearly see the difference between the older packings and the newer packings based on high-purity silicas. It is unquestionable today that surface silanols on a packing participate in the retention of basic analytes, and... 

RSDs of the retention relative to acenaphthene Propranolol Butylparabene Dipropylphthalate Naphthalene Amitriptyline... 

For the silanol interaction S, we found that the retention of amitriptyline corrected for the hydrophobic contribution to its retention is most suitable ... 

Amitriptyline is a tricylic antidepressant and these have antimuscarinic side-effects, such as urinary retention, blurred vision, dry mouth and sweating. They also tend to cause drowsiness. 

FIGURE 2.19 Influence of temperature on solute retention. Column ProntoSIL C18ACE, 125x4mm. Mobile phase MeOH/20mM phosphate buffer pH=7, 65/35 v/v. Samples 1, Uracil 2, propranolol 3, butylpa-raben 4, dipropylphthalate 5, naphthalene 6, acenaphthene 7, amitriptyline. 

The primary adverse effects of TCAs have been described in the previous text. Anticholinergic effects are perhaps the most common. These effects result in dry mouth, constipation, urinary retention, blurred vision, and confusion. They are more common with tertiary amine TCAs such as amitriptyline and imipramine than with the secondary amine TCAs desipramine and nortriptyline. The potent a-blocking property of TCAs often results in orthostatic hypotension. Hi... 

Broom 2. Ginkgo biloba 3. Scopolia 4. Yohimbine 1. TCAs (e.g. amitriptyline, nortriptyline, clomipramine) 2. SSRIs (e.g. fluvoxamine fluoxetine, paroxetine) 3. Venlafaxine 4. Trazodone May develop cardiac arrhythmias and side-effects such as dryness of the mouth, retention of urine and tachycardia, t sedation Broom contains cardioactive alkalamines such as sparteine Inhibits metabolizing enzymes Anticholinergic properties (hyoscine present in scopolia may worsen side-effects of TCAs-additive antimuscarinic effects) Yohimbine alone can cause hypertension, but lower doses cause hypertension when combined with TCAs Unknown mechanism (ginkgo t sedative effects of trazodone) St John s wort inhibits the uptake of serotonin and thereby t serotonin levels Avoid concomitant use. An SSRI may be a better alternative to be used with broom... 

Tricyclic antidepressants resemble the phenothiazine antipsychotics such as chlorpromazine in structure and function. Like the phenothiazine derivatives (e.g., chlorpromazine), tricyclic antidepressants (e.g., amitriptyline) may reduce the seizure threshold and precipitate seizures in epileptic patients, cause cholestatic jaundice, movement disorders, and hematologic side effects. Unlike the phenothiazine derivatives, the tricyclic antidepressants may increase motor activity, have a very slow onset and long duration of action, a relatively narrow margin of safety, and a strong anticholinergic effect. In fact, dry mouth is the most common side effect, and other anticholinergic effects such as tachycardia, loss of accommodation, constipation, urinary retention, and paralytic ileus have been reported following amitriptyline. 

Figure 20). Therefore, because of its pronounced anticholinergic and potential arrhythmogenic effects, amitriptyline is contraindicated in the acute recovery phase of myocardial infarction, congestive heart failure, angina, prostatic hypertrophy, paralytic ileus, and urinary retention, and in patients undergoing surgery with general anesthetics that may cause arrhythmias (e.g., halothane) (see Table 16).

The interactions with cimetidine are well established, well documented and of clinical importance. The incidence is uncertain hut most patients could be affected. Those taking amitriptyline, desipramine, doxepin, imi-pramine or nortriptyline who are given cimetidine should be warned that adverse effects such as mouth dryness, urine retention, blurred vision, constipation, tachycardia, postural hypotension may be more likely to occur. Other tricyclic antidepressants would be expected to be similarly affected. If symptoms are troublesome reduce the dosage of the antidepressant (33 to 50% has been suggested) or replace the cimetidine with ranitidine, which does not appear to interact. Other H2-ieceptor antagonists that do not cause enzyme inhibition (e.g. famotidine and nizatidine) would also not be expected to interact. 

Information seems to be limited to these reports. It would seem prudent to monitor for trieyolie adverse effeets (sueh as dry mouth, blurred vision and urinary retention) in patients given valproate and amitriptyline, clomipramine, or nortriptyline and to reduee the dosage of the tricyclic if necessary. Where possible eonsider monitoring tricyclic levels. Information about other trieyelie antidepressants seems to be lacking. The occurrence of status epileptieus in another patient reinforces the fact that the tricyclics can lower the eonvulsive threshold and should therefore be used with caution in patients with epilepsy. 

Casamenti et al. [1399] developed a method for screening 11 central nervous system drugs (phenobarbital, olanzapine, clozapine, risperidone, loxapine, haloperidol, imipramine, amitriptyline, fluoxetine, chlorpromazine, paroxetine) on a Cjg column (A = 230 nm) using a 20/11.7 water (0.4g tetramethylammonium perchlorate with 0.2 mL of 7% (m/m) HCIO4 to pH 2.8 with ammonia)/acetonitrile mobile phase. Keep in mind that perchlorates, when concentrated with some metals, are hazardous. Elution was complete in 35 min with good resolution for most compounds. Plots of the effects of mobile phase modifier level and percent acetonitrile on overall retention are presented. Linear ranges of 25-5000 ng/mL with detection limits of 10-250 ng/mL (analyte dependent) are reported. 

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