Citalopram; Uses, Dosage, Side Effects, Interactions, Pregnancy

Citalopram is a bicyclic naphthalene derivative and selective serotonin reuptake inhibitor (SSRI), with antidepressant and anxiolytic activities. Citalopramselectively inhibits the neuronal reuptake of the neurotransmitter serotonin (5-HT) in presynaptic cells in the central nervous system, thereby increasing levels of 5-HT within the synaptic cleft and enhancing the actions of serotonin on its receptors. Increased serotonergic neurotransmission results in antidepressive and anxiolytic effects.

Citalopram is an antidepressant medication belonging to a group of drugs called selective serotonin reuptake inhibitors (SSRIs) that affects neurotransmitters, the chemicals that nerves within the brain use to communicate with each other. Neurotransmitters are manufactured and released by nerves and then travel and attach to nearby nerves. Thus, neurotransmitters can be thought of as the communication.

Mechanism of Action of Citalopram 

The antidepressant, antiobsessive-compulsive, and antibulimic actions of citalopram are presumed to be linked to its inhibition of CNS neuronal uptake of serotonin. Citalopram blocks the reuptake of serotonin at the serotonin reuptake pump of the neuronal membrane, enhancing the actions of serotonin on 5HT_1A autoreceptors. SSRIs bind with significantly less affinity to histamine, acetylcholine, and norepinephrine receptors than tricyclic antidepressant drugs. The antidepressant, antiobsessive-compulsive, and antibulimic actions of citalopram are presumed to be linked to its inhibition of CNS neuronal uptake of serotonin. In vitro studies show that citalopram is a potent and selective inhibitor of neuronal serotonin reuptake and has only very weak effects on norepinephrine and dopamine neuronal reuptake. Citalopram has no significant affinity for adrenergic (α₁, α₂, β), cholinergic, GABA, dopaminergic, histaminergic, serotonergic (5HT_1A, 5HT_1B, 5HT₂), or benzodiazepine receptors; antagonism of such receptors has been hypothesized to be associated with various anticholinergic, sedative, and cardiovascular effects for other psychotropic drugs.

Indications of Citalopram 

• Anxiety and Stress
• Body Dysmorphic Disorder
• Depression
• Bipolar Disorder
• Postpartum Depression
• Agitation
• Borderline Personality Disorder
• Dissociative Identity Disorder
• Generalized Anxiety Disorder
• Neuralgia
• Anorexia Nervosa (AN)
• Bulimia Nervosa (BN)
• Diabetic Neuropathies
• Major Depressive Disorder (MDD)
• Obsessive Compulsive Disorder (OCD)
• Panic Disorders
• Post-Traumatic Stress Disorder (PTSD)
• Premature Ejaculation
• Premenstrual Dysphoric Disorder
• Social Anxiety Disorder (SAD)
• Obsessive Compulsive Disorder
• Occipital Neuralgia
• Panic Disorder
• Persistent Depressive Disorder
• Premenstrual Dysphoric Disorder
• Severe Mood Dysregulation
• Somatoform Pain? Disorder
• Trichotillomania
• For the treatment of depression. Off-label indications include: treatment of mild dementia-associated agitation in nonpsychotic patients, smoking cessation, ethanol abuse, obsessive-compulsive disorder (OCD) in children, and diabetic pain?, numbness?, tingling, or weakness?. সহজ বাংলা: স্নায়ুর ক্ষতি/সমস্যা।" data-rx-term="neuropathy" data-rx-definition="Neuropathy means nerve damage or irritation causing pain, numbness, tingling, or weakness. সহজ বাংলা: স্নায়ুর ক্ষতি/সমস্যা।">neuropathy?

Contra-Indications of Citalopram 

• Syndrome of Inappropriate Antidiuretic Hormone Secretion
• low amount of magnesium in the blood
• low amount of sodium in the blood
• low amount of potassium in the blood
• increased risk of bleeding
• Manic-Depression
• Having Thoughts of Suicide
• Neuroleptic Malignant? Syndrome
• serotonin syndrome – adverse drug interaction
• closed angle glaucoma
• heart attack within the last 30 days
• Very Rapid Heartbeat – Torsades de Pointes
• Slow Heartbeat
• prolonged QT interval on EKG
• chronic? heart failure
• chronic? heart failure suddenly not controlled by medication
• Heart Disease
• Abnormal EKG with QT changes from Birth
• liver problems
• Bleeding from Stomach
• Esophagus or Duodenum
• severe renal? impairment
• seizures

Dosages of Citalopram 

Strengths: 10 mg/5 mL; 10 mg; 20 mg; 40 mg

Depression

• Initial dose: 20 mg orally once a day
• Maintenance dose: 20 to 40 mg orally once a day
• Maximum dose: 40 mg orally per day

Geriatric Dose for Depression

Over 60 years of age

• Recommended dose: 20 mg orally once a day

Side Effects of Citalopram

The most common 

• The decrease in sexual desire or ability
• sleepiness or unusual drowsiness
• clumsiness or unsteadiness
• dizziness
• drowsiness
• dry mouth
• false sense of well-being
• increased watering of mouth
• lightheadedness
• constipation;
• vision changes;
• breast swelling (in men or women); or
• decreased sex drive, impotence, or difficulty having an orgasm.
• blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• restless muscle movements in your eyes, tongue, jaw, or neck;
• a light-headed feeling, like you, might pass out;

Common

• Drowsiness and lightheadedness the day after taking the medicine.
• Confusion.
• Numbed emotions.
• Visual disturbances such as blurred vision or double vision.
• Shaky movements and unsteady walk (ataxia).
• Loss of memory (amnesia).
• Muscle weakness.
• Dizziness.
• Headache.
• Skin rashes.
• Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain.
• Difficulty in passing urine (urinary retention).
• Changes in sex drive.
• Low blood pressure (hypotension).
• Blood disorders.
• Jaundice?.
• Unexpected aggression, restlessness or irritability (tell your doctor if you experience this).
• Nightmares or hallucinations (tell your doctor if you experience this).

Serious

• agitation
• anxiety
• behavioral changes, including aggressiveness, angry outbursts, bizarre behavior, or decreased inhibitions
• confusion
• increased trouble sleeping
• memory problems
• muscle spasms
• shortness of breath
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• sleepwalking

Drug Interactions of Citalopram

Citalopram may interact with following drugs, supplements & may change the efficacy of drugs

• amlodipine
• general anesthetics
• antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
• antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
• aripiprazole
• baclofen
• barbiturates (e.g., butalbital, pentobarbital, phenobarbital)
• benzodiazepines (e.g., alprazolam, diazepam, lorazepam)
• bupropion
• celecoxib
• cilostazol
• clopidogrel
• cyclosporine
• diabetes medications (e.g., chlorpropamide, metformin, nateglinide, rosiglitazone)
• diltiazem
• estrogens (e.g., conjugated estrogen, )
• glucosamine
• heparin
• low molecular weight heparins
• mirtazapine
• monoamine oxidase inhibitors (MAOIs; e.g. rasagiline, selegiline, )
• multivitamins
• muscle relaxants
• nifedipine
• non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, naproxen)
• omega-3 fatty acids
• pentoxifylline
• propranolol
• quinolone antibiotics (e.g., ciprofloxacin, norfloxacin, ofloxacin)
• rasagiline
• seizure medications ( phenobarbital, phenytoin, valproic acid, )
• selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, duloxetine, fluoxetine, paroxetine, sertraline)
• serotonin antagonists (anti-emetic medications; e.g., granisetron, ondansetron)
• tapentadol
• theophyllines  (e.g., aminophylline, oxtriphylline, theophylline)
• thiazide diuretics (water pills; e.g., hydrochlorothiazide, )
• thyroid? replacements (e.g., desiccated thyroid, levothyroxine)
• tizanidine
• tramadol
• tricyclic antidepressants (e.g., desipramine, nortriptyline)
• triptans (e.g., sumatriptan, rizatriptan)

Pregnancy & Lactation of Citalopram

FDA Pregnancy Category C

Pregnancy

This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Lactation

This medication passes into breast milk. If you are a breastfeeding mother and are taking citalopram, it may affect your baby. Talk to your doctor about whether you should continue breastfeeding. The safety and effectiveness of using this medication have not been established for children and is not indicated for use in children under the age of 18.

References