Review of Pharmacology - 9E (2015)

Review of Pharmacology
Central Nervous System
• Patients discontinued for WBC count less than 2000/mm 3 or absolute neutrophil count below 1000/mm 3 should not
be started on Clozapine again.
149. Ans. (a) Doxepin (Katzung 11/e p519)
• Serotonin and dopaminergic receptor blocking drugs are used for treatment of psychosis. Amisulpiride, sertindole
and zotepine are antipsychotic drugs acting by this mechanism. On the other hand, doxepin is an antidepressant and
do not block serotonin and dopaminergic receptors, rather it can inhibit the reuptake of serotonin and noradrenaline.
It also has strong antihistaminic and anticholinergic property.
150. Ans. (a) Imipramine (Ref: CMDT 2010/966)
Imipramine is efficacious however, Desmopressin is the first choice drug for nocturnal enuresis.
151. Ans. (c) Start SSRI treatment based on side effect profile (Ref: CMDT 2010/964)
• Depression associated with reactive disorders usually does not call for drug therapy and can be managed by
psychotherapy and the passage of time. In severe cases—particularly when vegetative signs are significant and
symptoms have persisted for more than a few weeks—antidepressant drug therapy is often effective. Drug therapy
is also suggested by a family history of major depression in first-degree relatives or a past history of prior episodes.
• Drug selection is influenced by the history of previous responses if that information is available. If a relative has
responded to a particular drug, this suggests that the patient may respond similarly. If no background information is
available, a drug such as sertraline, 25 mg orally daily and increasing gradually up to 200 mg orally, or desipramine,
starting with 50 mg orally and gradually increasing to 150 mg daily, can be selected and a full trial instituted. The
medication trial should be monitored for worsening mood or suicidal ideation with patient assessments every 1–2
weeks until week 6. If successful, the medication should be continued for 6–12 months at the full therapeutic dose
before tapering is considered.
152. Ans. (d) Diuretics (Ref: Katzung 11/e p502-503)
Most of the renal tubular reabsorption of Li + occurs in the proximal tubule. Nevertheless, Li + retention can be increased by
any diuretic that leads to depletion of Na + , particularly the thiazides.
153. Ans. (a) Acute Dystonia (Ref: Katzung 11/e p497)
• Dystonias are brief or prolonged contractions of muscles that result in obviously abnormal movements or postures,
including oculogyric crises, tongue protrusion, trismus, torticollis, laryngeal-pharyngeal dystonias, and dystonic
postures of the limbs and trunk. These are earliest appearing extrapyramidal symptoms with antipsychotic drugs.
154. Ans. (b) Cardiac malformations. (Ref: Katzung, 11/e p500, Goodman and Gilman, 11/e p1326)
• Lithium, if taken during pregnancy, can cause Ebstein’s anomaly in the fetus, which is a congenital heart disease
presenting as tricuspid atresia.
155. Ans. (b) Fluoxetine (Ref: Harrison 17/e p2715, CMDT 2010/943)
• SSRIs are drug of choice for most of the neurotic disorders including OCD.
156. Ans. (a) Clozapine (Ref: Goodman and Gilman 12th/440-441)
• Atypical antipsychotic drugs are implicated in causing adverse metabolic effects like weight gain, hyperlipidemia
and insulin resistance. According to their potential to cause these side effects, these can be classified as:
High Potential:
Intermediate potential:
Low Potential:
Least potential:
Clozapine, Olanzapine
Quetiapine
Risperidone, Paliperidone
Iloperidone, Aripiprazole, Asenapine, Ziprasidone
157. Ans. (d) Tianeptin (Ref: KDT 6/e p447)
• Tianeptin enhances the reuptake of serotonin rather than inhibiting it whereas the other drugs mentioned in the
options inhibit the reuptake of serotonin and nor-epinephrine.
158. Ans. (a) Premature ejaculation (Ref: Goodman and Gilman 12th/410-411)
378
• SSRIs can result in adverse effects like insomnia, anxiety, irritability and decreased libido due to excessive
stimulation of brain 5-HT 2
receptors.
• Excessive activity at spinal 5-HT 2
receptors causes sexual side effects including erectile dysfunction, anorgasmia
and ejaculatory delay, these are more prominent with paroxetine.
• Stimulation of 5-HT 3
receptors in the CNS and periphery contributes to GI effects which are usually limited
to nausea but can also result in diarrhea and emesis.
• Unlike other SSRIs, paroxetine is associated with an increased risk of congenital cardiac malformations.
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