Obsessive-compulsive disorder (OCD) is a disorder for which several treatment options are available, but it is also a condition that does not always respond satisfactorily and does not always respond quickly.
All medications that are useful for OCD are classified in the pharmaceutical market as “antidepressants,” but this should not lead one to think that the doctor has diagnosed depression, or that depression is otherwise involved. It is simply a pharmaceutical label that has remained unchanged for reasons of practicality.
All SSRIs are useful in OCD; overall, they are estimated to resolve about one case in two. There is stronger evidence in favor of clomipramine, fluvoxamine, and sertraline (considering not only their efficacy but also their comparative efficacy). The doses useful in OCD are in the medium-to-high range. It should be noted that doses are unfortunately expressed as oral doses, whereas it would be more appropriate to refer to the actual doses, that is, the concentrations in the blood. One of the most common factors underlying a “non-response” to treatment is an insufficient actual dose, even when the oral dose is at its maximum.
The time required to assess the course of the response is three months, also taking into account that treatment is not started immediately at the maximum dose, but that the dose is gradually increased. It has also been demonstrated that, during the first year, people who improve during the first few months may improve to a much greater extent if treatment is continued over the following months.
Some strategies for treating resistant cases appear to be little more than the equivalent of an even higher dose: for example, combining two SSRIs, combining an SSRI with an SNRI with a balanced mechanism of action, or administering the same medications by intravenous or intramuscular routes rather than orally.
Combining psychological and pharmacological interventions appears to be useful, particularly for maintaining the effect after discontinuation of treatment and when improvement with a single treatment was unsatisfactory but not entirely absent.
First-line treatments for OCD include two classes of antidepressants and several psychological techniques, which can also be combined, since there is evidence that their combination may increase efficacy, and there is in any case no evidence against combining them.
There is no general rule for choosing which class of antidepressant to start with, nor for deciding whether to begin with psychological or pharmacological treatment. The choice may vary according to several factors, including the characteristics of the disorder: whether it has been present for a short or long time, whether it is severe or mild, whether the rituals are overt or mental, and whether they involve neutralization rituals (doing something to counteract the concern) or avoidance rituals (not doing something in order to avoid anxiety).
One positive aspect of OCD treatment is that OCD does not respond to placebo, and therefore there is relatively little likelihood that a person will initially feel better through this mechanism, only for the improvement to subsequently fade.
After several attempts using first-line treatments and their possible combinations, OCD may be defined as “treatment-resistant.” This definition should not be a cause for despair. It simply introduces a series of alternatives for which there is no general evidence of usefulness in generic OCD, but which may be capable of improving cases that have not responded to established treatments.
It should be noted that some of these alternatives actually consist of introducing medications that act on other types of symptoms or mechanisms, because the person has OCD together with other disorders.
Sometimes, different tools are introduced from the outset precisely because OCD is not the only problem. Treating depression, bipolar disorder, or psychosis in a person who also has OCD may therefore also improve the symptoms of OCD.
Conversely, some treatments may worsen OCD or increase certain aspects of it, such as aggression when the person is challenged or prevented from performing rituals, the feeling of being unable to maintain control, and catastrophic thinking related to the inability to manage obsessions or the fear of going crazy, etc.
Treatments that may worsen OCD include, for example, some antidepressants and some psychological interventions.
Anti-OCD treatments normally cause anxiety and even OCD symptoms themselves to increase during the first two to three weeks. This does not mean that they are worsening the disorder; rather, reaching the final therapeutic effect involves an initial phase of brain adaptation during which symptoms may temporarily increase, or general worry may become more pronounced. Since people undergoing treatment naturally expect to see some sign of improvement immediately, and especially when they have a personality that tends toward control, seeing an initial worsening can be frightening or may lead them to believe that treatment is heading in completely the wrong direction. It is therefore important to know in advance what the course of treatment is likely to be during the first few weeks and to understand that the response generally does not begin to develop before about one month.