Final answer:
Selective Serotonin Reuptake Inhibitors (SSRIs) can be considered safe to use as first-line treatment for OCD.
Step-by-step explanation:
The class of drug that can be considered safe to use as first-line treatment for OCD is SSRI (Selective Serotonin Reuptake Inhibitors). SSRIs such as fluoxetine (Prozac), sertraline, and paroxetine selectively block the reuptake of serotonin in the central nervous system, thereby increasing serotonin levels. These drugs have been found to be effective in reducing the symptoms of OCD. It is important to note that caution should still be exercised when co-administering any drugs that affect serotonergic systems, such as monoamine oxidase inhibitors (MAOIs).