Medicines for OCD

Medicine is one of the two main treatments for obsessive-compulsive disorder (OCD). The other is a type of talk therapy called exposure and response prevention (ERP). Many people use one or the other. Some use both.

OCD medicines work best when you know what to expect. They are often used at higher doses than for depression, and they take weeks to show their full effect.^1,2 This page explains the main choices, what happens if the first one does not help, and how to stay safe, especially in later life.

How medicine helps OCD

OCD causes obsessions (unwanted thoughts, images or urges that keep coming back) and compulsions (things you feel you must do to ease the distress). You can read more on the OCD overview and signs of OCD pages.

The medicines that help OCD all act on serotonin (a chemical messenger in the brain). They do not erase obsessions. Instead, the thoughts often become quieter, less sticky and easier to ignore. That can make it easier to resist rituals and to do ERP.

Among people who respond to a medicine, symptoms drop by about 40% to 50% on average.¹ In daily life, that might mean an hour of checking each day instead of three, or being able to leave the house without a long routine. Most people still have some symptoms, so therapy and self-help skills remain useful.

SSRIs: the usual first choice

SSRIs (selective serotonin reuptake inhibitors) are the medicines doctors try first for OCD. Their side effects are usually milder than those of other OCD medicines.¹

Four SSRIs are approved by the U.S. Food and Drug Administration (FDA) for OCD:¹

Two other SSRIs, citalopram (Celexa) and escitalopram (Lexapro), also have good research support. Doctors sometimes use them even though they are not on the FDA list for OCD.¹ NICE lists several SSRIs as first choices without ranking them.⁴ The choice often depends on side effects, other health problems and other medicines you take.

For more on how these medicines work in general, see antidepressant medicines.

Why the dose is often higher

OCD tends to need higher SSRI doses than depression or anxiety. Some people need two to three times the usual depression dose.¹ A large review of nine trials, with more than 2,200 adults, found that higher doses helped more people than low or medium doses.³ But higher doses also led more people to quit because of side effects.³

So your doctor usually starts low and goes slow. The dose is raised step by step, watching how you feel. Do not raise or lower the dose yourself. Talk with your doctor or pharmacist before changing anything.

Why patience matters

OCD medicines are slow. It can take 8 to 12 weeks before you notice real change.² Experts say a fair trial lasts 8 to 12 weeks, with at least 6 of those weeks at a moderate to high dose.¹ Improvement can keep building after 12 weeks.¹

Many people give up too early because little seems to happen in the first month. Agree with your doctor on a check-in date.

Clomipramine (Anafranil)

Clomipramine was the first medicine proven to help OCD, and the first one the FDA approved for it.¹ It is a tricyclic antidepressant (an older type of antidepressant) with a strong effect on serotonin.

In the trials used for its approval, adults on clomipramine improved by roughly 35% to 42% on a standard OCD rating scale. People on placebo (a look-alike pill with no medicine) did not improve in any meaningful way.⁵ Strong evidence

Clomipramine has not been shown to work better than SSRIs, and it has more side effects. So doctors usually try it after one or two SSRIs have not helped.^1,4 Some people who did not respond to SSRIs do respond to clomipramine.¹

Its side effects are common. In adult OCD trials:⁵

• Dry mouth affected about 8 in 10 people.
• Sleepiness, dizziness and shaking (tremor) each affected about half.
• Constipation affected nearly half.
• Sexual problems, such as trouble with ejaculation, were common in men.

Clomipramine also carries more serious risks. It can cause seizures, and the risk rises with the dose.⁵ It can lower blood pressure when you stand up and speed up the heart.⁵ It is dangerous in an overdose.⁴ Doctors often check an EKG (a heart rhythm tracing), blood pressure and sometimes blood levels of the medicine.^1,4 People who have just had a heart attack should not take it.⁵

If the first medicine does not help enough

Not getting better on the first medicine is common. It does not mean you cannot be helped. Doctors usually work through steps like these:^1,4

1. Check the basics. Was the dose high enough, for long enough? Were doses missed? Are alcohol or other drugs getting in the way?
2. Add or increase ERP therapy. NICE, the U.K. guideline body, advises combining medicine with ERP when OCD seriously limits daily life.⁴ See ERP therapy.
3. Switch to a different SSRI or to clomipramine.
4. Add a second medicine (called augmentation), usually with a specialist's help.

Adding a second medicine (augmentation)

The add-on medicines with the most research are low-dose antipsychotics, especially aripiprazole (Abilify) and risperidone (Risperdal).¹ Antipsychotics are medicines first made for psychosis, but small amounts can boost the effect of an SSRI in OCD.

A review of nine trials looked at adults whose OCD had not improved enough on a serotonin medicine. About 1 in 3 had a meaningful response when an antipsychotic was added.⁷ People who also had tics (sudden, repeated movements or sounds) seemed to benefit more.⁷ The review authors suggested giving the first medicine at least 3 months at the highest dose a person can handle before adding one.⁷ Moderate evidence

Antipsychotics do not help OCD when used alone. They also carry more short- and long-term side effects than SSRIs.¹ NICE advises that a specialist team review the case before adding one.⁴ For older adults, especially people with memory problems, these medicines need extra care. See medicines for agitation and behavior.

Other add-on options include:

• Clomipramine added to an SSRI, sometimes at a lower dose to limit side effects.¹
• Medicines that act on glutamate (another brain chemical), such as memantine or N-acetylcysteine. The evidence is thinner, but side effects tend to be milder.¹ Limited research

Deep TMS: a magnetic treatment

Transcranial magnetic stimulation (TMS) uses magnetic pulses from a coil held against the head. The pulses stimulate brain areas linked to OCD. You stay awake, and no surgery or anesthesia is needed.

In August 2018, the FDA allowed the BrainsWay Deep TMS system to be marketed for OCD.⁸ It is meant as an add-on treatment for adults, alongside their usual care.⁹ Since then, the FDA has cleared other TMS devices for OCD as well.²

What the study showed. The main trial included 100 adults whose OCD had not improved enough with other treatment. After six weeks, about 38% of people on real TMS had a clear drop in symptoms (at least 30%). Only about 11% did on a sham (fake) device.⁸ That is a real benefit, but most people did not reach that level. Promising

What treatment is like. In the study, people came in five days a week for six weeks. Each visit took about 30 minutes. Before each session, staff briefly brought on some OCD distress on purpose, using each person's own triggers.⁹

Side effects. Headache was the most common, but it was almost as common with the sham device. Some people had scalp, jaw or neck discomfort that faded soon after treatment. No serious device-related problems were reported in the trial.⁸ Seizures are a rare risk with TMS, so people with a seizure history need caution.⁹

Who should not have it. TMS is not used in people with certain metal in or near the head, such as aneurysm clips, cochlear implants or brain stimulators.⁹

For very severe OCD that has not responded to anything else, deep brain stimulation (a surgery that places wires in the brain) is allowed under a special FDA pathway for rare uses. It is still considered experimental.² Limited research

Side effects and safety

Common SSRI side effects include nausea, loose stools, trouble sleeping, sleepiness, dizziness and sexual problems.⁶ If one bothers you, tell your doctor. A dose change or a different medicine may help.

All antidepressants, including those used for OCD, have an FDA boxed warning. They can raise the risk of suicidal thoughts in children, teens and young adults under 25. Doctors watch most closely in the first weeks and after any dose change.^5,6 In the FDA's data, adults 65 and older on antidepressants had fewer suicidal thoughts and behaviors than those on placebo, not more.⁶ Still, anyone of any age should report new or worse dark thoughts.

Do not mix without checking

SSRIs and clomipramine must never be taken with MAOIs (an older group of antidepressants), or within 14 days of one.^5,6 SSRIs also raise the risk of bleeding when taken with aspirin, NSAID pain relievers like ibuprofen, or blood thinners such as warfarin.⁶ Always give your doctor and pharmacist a full list of your medicines, including over-the-counter products and supplements.

Older adults: extra care

OCD medicines can be used in later life, but the body handles them differently. The labels for both sertraline and clomipramine advise starting at the low end of the dose range in older adults.^5,6 Some things to watch for:

• Low sodium (hyponatremia). SSRIs and clomipramine can lower blood sodium. Older adults and people taking water pills (diuretics) are at higher risk. Signs include headache, confusion, weakness and unsteadiness, which can lead to falls.^5,6
• Falls and dizziness. Clomipramine can lower blood pressure when standing.⁵
• Bleeding. Many older adults take aspirin or blood thinners, which add to the SSRI bleeding risk.⁶
• Memory and confusion. Clomipramine often causes drying effects such as dry mouth and constipation.⁵ If you or your family member has memory problems, ask whether it is a good fit. See medicines that can worsen memory.
• Eyes. Antidepressants can trigger a sudden type of glaucoma in people with narrow eye angles. Sudden eye pain or vision changes need urgent care.⁶

New OCD-like symptoms that start late in life deserve a careful medical checkup, because other conditions can look similar. If an older family member suddenly starts collecting and keeping large amounts of things, see hoarding disorder.

How long to stay on medicine, and stopping safely

OCD is usually a long-term condition. If a medicine helps, guidelines advise staying on it for at least 12 months before thinking about stopping.⁴ After that, you and your doctor can review whether to continue.

When the medicine stops, the benefit often stops too, and symptoms commonly return. Doing ERP may lower the chance of relapse after stopping.¹

If you and your doctor decide to stop, the dose is lowered slowly over several weeks.⁴ Stopping suddenly can cause dizziness, nausea, headache, irritability, sleep problems and a general sick feeling.^5,6 Talk with your doctor or pharmacist before changing anything.

Questions to ask your doctor

Is my dose high enough for OCD, not just for depression?

OCD often needs a higher dose. Ask where you are in the usual range and whether there is room to go up safely.

Should I also be doing ERP therapy?

For many people, medicine plus ERP works better than either alone, especially when OCD seriously limits daily life.⁴ The ERP page explains how to find a trained therapist.

What should my family do or not do?

Family members often help most by gently cutting back on reassurance and ritual help. See helping a family member with OCD and self-help for OCD.

Education only. This page is general information written from the sources listed. It is not medical, legal or financial advice and does not replace a doctor, therapist or lawyer who knows your situation. How we write and check pages.