The premarketing development program for citalopram tablets included citalopram exposures in patients and/or normal subjects from 3 different groups of studies: 429 normal subjects in clinical pharmacology/pharmacokinetic studies; 4422 exposures from patients in controlled and uncontrolled clinical trials, corresponding to approximately 1370 patient-exposure years. There were, in addition, over 19,000 exposures from mostly open-label, European postmarketing studies. The conditions and duration of treatment with citalopram tablets varied greatly and included (in overlapping categories) open-label and double-blind studies, inpatient and outpatient studies, fixed-dose and dose-titration studies, and short-term and long-term exposure. Adverse reactions were assessed by collecting adverse events, results of physical examinations, vital signs, weights, laboratory analyses, ECGs, and results of ophthalmologic examinations.
Adverse events during exposure were obtained primarily by general inquiry and recorded by clinical investigators using terminology of their own choosing. Consequently, it is not possible to provide a meaningful estimate of the proportion of individuals experiencing adverse events without first grouping similar types of events into a smaller number of standardized event categories. In the tables and tabulations that follow, standard World Health Organization (WHO) terminology has been used to classify reported adverse events.
The stated frequencies of adverse events represent the proportion of individuals who experienced, at least once, a treatment-emergent adverse event of the type listed. An event was considered treatment-emergent if it occurred for the first time or worsened while receiving therapy following baseline evaluation.
Adverse Findings Observed in Short-Term, Placebo-Controlled Trials
Adverse Events Associated with Discontinuation of Treatment
Among 1063 depressed patients who received citalopram tablets at doses ranging from 10 to 80 mg/day in placebo-controlled trials of up to 6 weeks in duration, 16% discontinued treatment due to an adverse event, as compared to 8% of 446 patients receiving placebo. The adverse events associated with discontinuation and considered drug-related (i.e., associated with discontinuation in at least 1% of citalopram tablets-treated patients at a rate at least twice that of placebo) are shown in
TABLE 2. It should be noted that one patient can report more than one reason for discontinuation and be counted more than once in this table.
Adverse Events Occurring at an Incidence of 2% or More Among Citalopram-Treated Patients
Table 3 enumerates the incidence, rounded to the nearest percent, of treatment-emergent adverse events that occurred among 1063 depressed patients who received citalopram tablets at doses ranging from 10 to 80 mg/day in placebo-controlled trials of up to 6 weeks in duration. Events included are those occurring in 2% or more of patients treated with citalopram tablets and for which the incidence in patients treated with citalopram tablets were greater than the incidence in placebo-treated patients.
The prescriber should be aware that these figures cannot be used to predict the incidence of adverse events in the course of usual medical practice where patient characteristics and other factors differ from those which prevailed in the clinical trials. Similarly, the cited frequencies cannot be compared with figures obtained from other clinical investigations involving different treatments, uses, and investigators. The cited figures, however, do provide the prescribing physician with some basis for estimating the relative contribution of drug and non-drug factors to the adverse event incidence rate in the population studied.
The only commonly observed adverse event that occurred in citalopram patients with an incidence of 5% or greater and at least twice the incidence in placebo patients was ejaculation disorder (primarily ejaculatory delay) in male patients (see
TABLE 3).
Dose Dependency of Adverse Events
The potential relationship between the dose of citalopram tablets administered and the incidence of adverse events was examined in a fixed-dose study in depressed patients receiving placebo or citalopram tablets 10, 20, 40, and 60 mg. Jonckheere’s trend test revealed a positive dose response (p<0.05) for the following adverse events: fatigue, impotence, insomnia, sweating increased, somnolence, and yawning.
Male and Female Sexual Dysfunction with SSRIs
Although changes in sexual desire, sexual performance, and sexual satisfaction often occur as manifestations of a psychiatric disorder, they may also be a consequence of pharmacologic treatment. In particular, some evidence suggests that SSRIs can cause such untoward sexual experiences.
Reliable estimates of the incidence and severity of untoward experiences involving sexual desire, performance, and satisfaction are difficult to obtain, however, in part because patients and physicians may be reluctant to discuss them. Accordingly, estimates of the incidence of untoward sexual experience and performance cited in product labeling, are likely to underestimate their actual incidence.
The table below displays the incidence of sexual side effects reported by at least 2% of patients taking citalopram tablets in a pool of placebo-controlled clinical trials in patients with depression.
In female depressed patients receiving citalopram tablets, the reported incidence of decreased libido and anorgasmia was 1.3% (n=638 females) and 1.1% (n=252 females), respectively.
There are no adequately designed studies examining sexual dysfunction with citalopram treatment.
Priapism has been reported with all SSRIs.
While it is difficult to know the precise risk of sexual dysfunction associated with the use of SSRIs, physicians should routinely inquire about such possible side effects.
Vital Sign Changes
Citalopram tablets and placebo groups were compared with respect to (1) mean change from baseline in vital signs (pulse, systolic blood pressure, and diastolic blood pressure) and (2) the incidence of patients meeting criteria for potentially clinically significant changes from baseline in these variables. These analyses did not reveal any clinically important changes in vital signs associated with citalopram hydrobromide treatment. In addition, a comparison of supine and standing vital sign measures for citalopram tablets and placebo treatments indicated that citalopram tablets treatment is not associated with orthostatic changes.
Weight Changes
Patients treated with citalopram tablets in controlled trials experienced a weight loss of about 0.5 kg compared to no change for placebo patients.
Laboratory Changes
Citalopram tablets and placebo groups were compared with respect to (1) mean change from baseline in various serum chemistry, hematology, and urinalysis variables, and (2) the incidence of patients meeting criteria for potentially clinically significant changes from baseline in these variables. These analyses revealed no clinically important changes in laboratory test parameters associated with citalopram tablets treatment.
ECG Changes
Electrocardiograms from citalopram tablets (N=802) and placebo (N=241) groups were compared with respect to (1) mean change from baseline in various ECG parameters, and (2) the incidence of patients meeting criteria for potentially clinically significant changes from baseline in these variables. The only statistically significant drug-placebo difference observed was a decrease in heart rate for citalopram tablets of 1.7 bpm compared to no change in heart rate for placebo. There were no observed differences in QT or other ECG intervals.
Other Events Observed During the Premarketing Evaluation of Citalopram Tablets
Following is a list of WHO terms that reflect treatment-emergent adverse events, as defined in the introduction to the
ADVERSE REACTIONS section, reported by patients treated with citalopram tablets at multiple doses in a range of 10 to 80 mg/day during any phase of a trial within the premarketing database of 4422 patients. All reported events are included except those already listed in
Table 3 or elsewhere in labeling, those events for which a drug cause was remote, those event terms which were so general as to be uninformative, and those occurring in only one patient. It is important to emphasize that, although the events reported occurred during treatment with citalopram tablets, they were not necessarily caused by it.
Events are further categorized by body system and listed in order of decreasing frequency according to the following definitions: frequent adverse events are those occurring on one or more occasions in at least 1/100 patients; infrequent adverse events are those occurring in less than 1/100 patients but at least 1/1000 patients; rare events are those occurring in fewer than 1/1000 patients.
Cardiovascular - Frequent: tachycardia, postural hypotension, hypotension.
Infrequent: hypertension, bradycardia, edema (extremities), angina pectoris, extrasystoles, cardiac failure, flushing, myocardial infarction, cerebrovascular accident, myocardial ischemia.
Rare: transient ischemic attack, phlebitis, atrial fibrillation, cardiac arrest, bundle branch block.
Central and Peripheral Nervous System Disorders - Frequent: paresthesia, migraine.
Infrequent: hyperkinesia, vertigo, hypertonia, extrapyramidal disorder, leg cramps, involuntary muscle contractions, hypokinesia, neuralgia, dystonia, abnormal gait, hypesthesia, ataxia.
Rare: abnormal coordination, hyperesthesia, ptosis, stupor.
Endocrine Disorders - Rare: hypothyroidism, goiter, gynecomastia.
Gastrointestinal Disorders - Frequent: saliva increased, flatulence.
Infrequent: gastritis, gastroenteritis, stomatitis, eructation, hemorrhoids, dysphagia, teeth grinding, gingivitis, esophagitis.
Rare: colitis, gastric ulcer, cholecystitis, cholelithiasis, duodenal ulcer, gastroesophageal reflux, glossitis, jaundice, diverticulitis, rectal hemorrhage, hiccups.
General -
Infrequent: hot flushes, rigors, alcohol intolerance, syncope, influenza-like symptoms.
Rare: hayfever.
Hemic and Lymphatic Disorders - Infrequent: purpura, anemia, epistaxis, leukocytosis, leucopenia, lymphadenopathy.
Rare: pulmonary embolism, granulocytopenia, lymphocytosis, lymphopenia, hypochromic anemia, coagulation disorder, gingival bleeding.
Metabolic and Nutritional Disorders - Frequent: decreased weight, increased weight.
Infrequent: increased hepatic enzymes, thirst, dry eyes, increased alkaline phosphatase, abnormal glucose tolerance.
Rare: bilirubinemia, hypokalemia, obesity, hypoglycemia, hepatitis, dehydration.
Musculoskeletal System Disorders - Infrequent: arthritis, muscle weakness, skeletal pain.
Rare: bursitis, osteoporosis.
Psychiatric Disorders - Frequent: impaired concentration, amnesia, apathy, depression, increased appetite, aggravated depression, suicide attempt, confusion.
Infrequent: increased libido, aggressive reaction, paroniria, drug dependence, depersonalization, hallucination, euphoria, psychotic depression, delusion, paranoid reaction, emotional lability, panic reaction, psychosis.
Rare: catatonic reaction, melancholia.
Reproductive Disorders/Female* - Frequent: amenorrhea.
Infrequent: galactorrhea, breast pain, breast enlargement, vaginal hemorrhage.
* % based on female subjects only: 2955
Respiratory System Disorders - Frequent: coughing.
Infrequent: bronchitis, dyspnea, pneumonia.
Rare: asthma, laryngitis, bronchospasm, pneumonitis, sputum increased.
Skin and Appendages Disorders - Frequent: rash, pruritus.
Infrequent: photosensitivity reaction, urticaria, acne, skin discoloration, eczema, alopecia, dermatitis, skin dry, psoriasis.
Rare: hypertrichosis, decreased sweating, melanosis, keratitis, cellulitis, pruritus ani.
Special Senses - Frequent: accommodation abnormal, taste perversion.
Infrequent: tinnitus, conjunctivitis, eye pain.
Rare: mydriasis, photophobia, diplopia, abnormal lacrimation, cataract, taste loss.
Urinary System Disorders - Frequent: polyuria.
Infrequent: micturition frequency, urinary incontinence, urinary retention, dysuria.
Rare: facial edema, hematuria, oliguria, pyelonephritis, renal calculus, renal pain.