Withdrawal from antidepressants

The reason for this warning is that abrupt cessation of SSRIs produces withdrawal symptoms in about 20 per cent of patients. Symptoms of withdrawal from antidepressant medication include gastrointestinal disturbances (abdominal cramping and pain, diarrhoea, nausea and vomiting), flu-like symptoms, headaches, sleep disturbances, dizziness, blurred vision, numbness, electric-shock sensations, twitches and tremors. Abrupt withdrawal can also produce symptoms of depression and anxiety, which can occur within hours of the first missed dose of the drug.11 Withdrawal symptoms are sometimes mistaken for a relapse, leading patients to resume antidepressant medication and to conclude that they need it in order to remain free of depression. Technically, this is not considered addiction , but it does seem awfully close. 

Nicotine is responsible for the highly addictive properties of tobacco products. Addiction occurs in 30% of those who experiment with tobacco products, and more than 80% of those who attempt to quit smoking will relapse within a year. Withdrawal from nicotine produces a syndrome characterized by nicotine craving as well as dysphoria, anxiety, irritability, restlessness and increased appetite. It is treated with nicotine replacement therapies, such as nicotine gum and patches, and/or with buproprion, a drug that is classified as an antidepressant but has multiple and complex effects in brain. Buproprion reduces craving in some smokers. Nicotine addiction has been reviewed recently at cellular and systems levels [38-41]. 

Desipramine has been used to facilitate withdrawal from chronic PCP use. The rationale is that PCP depletes norepinephrine concentrations in brain, and that this tricyclic antidepressant is the most selective blocker of norepinephrine uptake. Consequently, some of the deficiency of the neurotransmitter could be remedied. A dose of 25 to 50 mg was said to reduce craving for several hours. Six of eight patients treated with this drug were successfully withdrawn, while none of the eight offered other types of programs were successful (45). 

Antidepressants differ from benzodiazepines in the onset and course of their actions (Fig. 2). Most cause an increase in anxiety on initiation of therapy, and anxiolytic effects occur later. In comparative studies, improvement matches that on benzodiazepines after 4 weeks (Rocca et al. 1997). Withdrawal effects, particularly rebound, are less problematic with antidepressants, although stopping treatment is associated with a significant rate of relapse, and a withdrawal syndrome has been described for most of the shorter-acting drugs. 

Tricyclic antidepressants also have a documented syndrome associated with withdrawal from medications (Petti and Law, 1981). This syndrome can mimic appendicitis or the flu, and can include such symptoms as nausea and vomiting, headache, lethargy, and abdominal pain. If a child on TCAs presents with withdrawal symptoms, questions of compliance must be addressed. 

Antidepressants appear sometimes useful in aiding withdrawal attempts, rather as they can he in withdrawal from benzodiazepines or alcohol. There is some positive evidence for serotonin re-uptake inhibitors and nortriptyline, but the strongest is for bupropion, which in the UK at least is the only antidepressant licensed for use as a cessation aid. Success rates for this seem to be very similar to those with nicotine replacement, approximately doubling a smoker s chances (Hughes et al. 2007). The latest option is varenicline, which acts as a partial agonist on one of the nicotinic receptors. 

Among the many toxicants that cause convulsions are chlorinated hydrocarbons, amphetamines, lead, organophosphates, and strychnine. There are several levels of coma, the term used to describe a lowered level of consciousness. At level 0, the subject may be awakened and will respond to questions. At level 1, withdrawal from painful stimuli is observed and all reflexes function. A subject at level 2 does not withdraw from painful stimuli, although most reflexes still function. Levels 3 and 4 are characterized by the absence of reflexes at level 4, respiratory action is depressed and the cardiovascular system fails. Among the many toxicants that cause coma are narcotic analgesics, alcohols, organophosphates, carbamates, lead, hydrocarbons, hydrogen sulfide, benzodiazepines, tricyclic antidepressants, isoniazid, phenothiazines, and opiates. 

The older tricyclic antidepressants and monoamine oxidase inhibitors also cause withdrawal mania and a variety of other adverse withdrawal effects, including cognitive and emotional disturbances and psychosis. Many of them have strong anticholinergic effects and therefore produce severe anticholinergic rebound on withdrawal, including cardiovascular and gastrointestinal symptoms. I have seen patients who have taken tricyclics for many years and then been unable to withdraw from them. 

McMahon, T. C. (1986). A clinical overview of syndromes following withdrawal from antidepressants. Hospital and Community Psychiatry, 37, 883-884. 

Another report has suggested that effects in the neonate may be due to withdrawal from maternal antidepressants after birth (136). Two cases of neonatal convulsions have been reported in infants whose mothers had been treated with clomipramine. In both cases the seizures occurred on the first day of life coincident with a fall in plasma clomipramine concentrations. In one case the convulsions were controlled by administration of clomipramine followed by tapered withdrawal. 

Tyrer P. Clinical effects of abrupt withdrawal from tricyclic antidepressants and monoamine oxidase inhibitors after long-term treatment. J Affect Disord 1984 6(l) l-7. 

Imipramine (brand name Tofranil) Often referred to as the grandfather of all antidepressants. It is the oldest tricyclic antidepressant available and has traditionally been used for the treatment of depression and for those who have panic attacks. It is sometimes used now to assist with withdrawal from cocaine addiction and in obsessive-compulsive disorder. 

In addition, withdrawal from certain medications, such as baclofen, clonidine, corticosteroids, or tricyclic antidepressants, may cause manic symptoms. 

Tricyclics modify peripheral sympathetic effects in two ways through blockade of norepinephrine reuptake at neuroeffector junctions and through alpha adrenoceptor blockade. Sedation and atropine-like side effects are common with tricyclics, especially amitriptyline. In contrast to sedative-hypnotics, tricyclics lower the threshold to seizures. The answer is (B). Selective serotonin reuptake inhibitors cause sexual dysfunction in some patients, with changes in libido, erectile dysfunction, and anorgasmia. Tricyclic antidepressants may also decrease libido or prevent ejaculation. Of the heterocyclic antidepressants bupropion is the least likely to affect sexual performance. The drug is also used in withdrawal from nicotine dependence. The answer is (B). 

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