Protriptyline side effects

Tricyclic Antidepressants (TCAs). TCAs were introduced in the 1950s and over the years have become the mainstay of treatment for cataplexy and the other REM-related symptoms. The doses used are usually less than the doses required in the treatment of depression. Imipramine (Tofranil) is the most widely used TCA for narcolepsy and is usually effective at doses from 10 to 75 mg given once a day. Some doctors prefer the TCA protriptyline (Vivactil) because it has mild stimulant effects, but it has not been as widely used or as thoroughly studied in narcolepsy. The common side effects of TCAs are drowsiness, dry mouth, and constipation, but these are usually not a problem at the lower doses used for narcolepsy. Patients should receive a baseline electrocardiograph (EKG) before starting a TCA and should have blood levels of the medication checked periodically. 

The metabolism and elimination of TCAs takes several days to occur, the elimination half-life ranging from 20 hours for amitriptyline to 80 hours for protriptyline. The half-life values for the desmethylated metabolites such as desmethylimipramine and nortriptyline are approximately twice those of the parent compounds imipramine and amitriptyline. It is also well established that the half-life values of the TCAs are considerably greater in the elderly, which predisposes such patients to a greater possibility of severe side effects. 

Reboxetine is the only selective and reasonably potent noradrenaline reuptake inhibitor available clinically at the present time. Reboxetine has a chemical structure not dissimilar from viloxazine, an antidepressant which was of only limited clinical interest in the 1970s because of its weak efficacy and unacceptable side effects (nausea, vomiting and occasionally seizures). Unlike the secondary amine TCA antidepressants, such as maprotiline, desipramine, nortriptyline and protriptyline, reboxetine does not affect any other transporter or receptor system and therefore is largely devoid of TCA and SSRI-like side effects. In clinical trials, reboxetine has been shown to be as effective as the SSRIs in the... 

Imipramine, amitriptyline, clomipramine, trimipramine, and doxepin are tertiary amine TCAs. Desipramine, nortriptyline, and protriptyline are secondary amine TCAs. Tertiary amine tricyclics have more potent serotonin reuptake inhibition, and secondary amine tricyclics have more potent noradrenergic reuptake inhibition. Tertiary amine TCAs tend to have more side effects than do... 

Anticholinergic side effects result from antagonism of muscarinic receptors. The most common anticholinergic side effects are dry mouth, constipation, urinary retention, blurred vision, and tachycardia. In predisposed patients, such as elderly persons, anticholinergic medications may cause cognitive impairment and confusion. Because the tertiary amines and protriptyline have a particularly high affinity for muscarinic receptors, these medications are more likely than others to have anticholinergic side effects. 

BW 247 and protriptyline were Inactive.75 bw 247 (15) is a ring-opened TCA with few anticholinergic effects and a profile of mixed NA and 5-HT uptake inhibition. It is structurally related to several potential antidepressants, including AHR 1118 (16). Both 1 and 1 are effective antidepressants in man 6 showed fewer side-effects than imipramine in a... 

Antidepressants with sedation as a side effect often are used to treat insomnia. The antidepressants most frequently associated with sedation as a side effect are the tricyclics (amitryptyline, imipramine, nortriptyline, trimipramine, doxepin, amoxapine, and protriptyline), nontricyclics (maprotiline and mirtazepine), trazodone, and nefazodone (55), which are discussed in greater detail in Chapter 21. Of these drugs, trazodone, doxepin, and mirtazepine have been shown to be effective in the treatment of insomnia in patients with depression (1). The effectiveness of these drugs to treat insomnia in nondepressed patients, however, has not been proven. The mechanism by which this occurs is unknown, but most of these drugs have some activity as H2 antagonists that may contribute to the effect (56). 

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