Side Effects

Question 1

Serotonin Syndrome

Answer 1

Over-stimulation of the serotonergic system that can result from the following combinations:

• SSRI + MAOI (or swtiching from one to the other)
• SSRI + tryptophan
• MAOI + tryptophan
• MAOI + Meperidine (painkiller)

Symptoms:
nausea, diarrhea, palpations, chills, restlessness, confusion, lethargy, that then lead to myoclonus, hyperthermia, rigor, and hypertonicity.

Treatment is to discontinue medication and give medical care ASAP.

Question 2

Discontinuation Syndrome

Answer 2

Cuased by the abrupt cessation of an antidepressant. Most commonly seen with fluvoxamine, paroxetine, and vanlafaxine.

Symptoms:
begin within 1-3 days and include anxiety, insomnia, irritability, mood lability, N/V, dizziness, headache, dystonia, tremor, chills, fatigue, lethargy, and myalgias.

Treatment:
symptoms may last 103wks but can be relived in 24hrs by restarting antidepressant therapy at the same dose the patient was taking and initiating a slow taper over several weeks.
Occurs less frequently with long half life drugs like fluoxetine.

Question 3

Extrapyramidal Symptoms (EPS)

Answer 3

Typical APs drug induced movement disorders including: acute dystonia (abnormal muscle tone resulting in spasm and abnormal posture), akathisia, akinesia, tardive dyskinesia (involuntary movements of the face and jaw but may be the whole body in a S-like movement).

Acute EPS are dystonia, akathisia, and akinesia. Long term EPS is usually TD.

EPS are very distressing to patients and must be treated either by removal of the typical AP or by treating symptoms.

Acute dystonia/Parkinsonism: cogentin/amantidine/Benadryl (anticholinergics) 1-2mg IM stat

Akathisia: clonazepam +/- propanolol

TD: lower the dose of the typical AP and swtich to a typical; +/- clozapine

Question 4

Neuroleptic Malignant Syndrome (NMS)

Answer 4

A rare but potentially lethal side effect of both typical and atypical APs due to a massive dopamine blockade. A psychiatric EMERGENCY.

Symptoms include: mental status changes (usually the first symptom), fever, autonomic dysfunction (increased HR, BP and sweating), rigidity, leukocytosis, and increased creatinine phosphokinase.

Treatment: d/c drug, hydration, cooling blankets, dantrolene (muscle relaxant), and bromocryptine (dopamine agonist).

Question 5

Side effects of Typical APs

Answer 5

muscle stiffness
muscle cramping
tremors
dry mouth
weight gain
EPS and Parkinsonism (more than in atypicals)
rarely NMS

Question 6

Side effects of Atypical APs

Answer 6

Anticholinergic
-dry mouth
-confusion
-dry eyes
-urinary stasis
(BLIND as a BAT, RED as a BEET, HOT as a HARE, DRY as a BONE, MAD as a HATTER)

Antihistaminic

• sedation
• weight gain (metabolic changes)

Antiadrenergic

• orthostatic hypotension
• erectile dysfunction

Metabolic side effects

• T2DM
• weight gain
• cholesterol changes

Cardiac
-prolonged QT

rarely NMS

Question 7

Side effects of SSRIs

Answer 7

Nausea, diarrhea, weight fluctuations, sexual dysfunction (erectile dysfunction and anoragsmia in women), headache, dizziness, sleep disturbance, SIADH in the elderly.

Question 8

Side effects of SNRIs

Answer 8

Same as SSRIs + increased BP (~5mmHg)

Question 9

Side effects of NaSAA (Mirtazepine)

Answer 9

weight gain and sedation

Question 10

Side effect of NDRI (Wellbutrin)

Answer 10

lowers seizure threshold

*benefits compared to SSRIs are less sexual dysfunction and can be used a nicotine replacement

Question 11

Side effects of Valproic Acid

Answer 11

elevated liver enzymes, skin rash (rare Steven Johnson syndrome), and teratogenic (neural tube defects).

Question 12

Side effects of Lithium

Answer 12

-leukocytosis
-weight gain
-hypothyroidism
-tremor
-teratogenic (Ebstein’s anomaly causing congenital heart defects in the newborn)
-nephrogenic diabetes mellitus
-N/V
-cardiac side effects (SA node dysfunction)
-acne
-psoriasis
-toxicity can result if levels are not monitored:
ataxia, dysarthria, myoclonus, mental status changes, seizures, and coma
*dialyze if serum level is >2