What to expect when you’re on antidepressants

If you’ve been prescribed antidepressants by your GP for your mental health, then you might have a few questions around what to expect when you start taking them. Sony Rai, registered pharmacist in our 24/7 health support team, for members, explores some common concerns around antidepressants, from the potential side effects to how and when to safely come off them.

>Read our article on what to know before starting antidepressants, if you have any questions around the types available and how they work.

What dosage will I be given?

There’s no standard dosage for antidepressants, and it’ll be adjusted based on:

• your medical history,
• any interactions with current medications,
• and your age.

Typically, when starting antidepressants, you’ll begin with the lowest dose. This approach aims to achieve an effective therapeutic response while minimising side effects.

Antidepressants aren’t one-size-fits-all. For instance, a daily dose of Sertraline 50 mg may work well for one person but not for another.

If a particular combination of antidepressants doesn’t produce positive results, it’s important not to be discouraged, as this doesn’t mean antidepressants are ineffective. It just reinforces why attending follow-up appointments after the initiation of treatment is important, as your prescriber will evaluate your progress and decide if any adjustments to your dosage or medication are necessary.

How do I know if my antidepressants are working?

As it can take a few weeks to see benefits, it’s vital not to miss any doses during this period. You may notice improvements in your symptoms such as improvements in mood, energy, concentration and sleep.

Don’t be disheartened if you don’t notice any changes. As mentioned above, speak to your prescriber to discuss your treatment plan.

Do antidepressants cause side effects?

All medications can cause side effects, usually lasting only the first few weeks as your body adjusts.

After this initial period, side effects may diminish. The long-term benefits of antidepressants often outweigh the risks associated with these early side effects, so it’s important to keep your prescriber informed if you experience them.

Common side effects of selective serotonin reuptake inhibitors (SSRIs) and Serotonin and noradrenaline reuptake inhibitors (SNRIs)

• Headaches
• Dizziness
• Feeling agitated or anxious
• Nausea
• Gastrointestinal issues (stomach cramps, diarrhoea, constipation)
• Loss of appetite
• Sleep changes (insomnia or increased drowsiness)
• Sexual dysfunction (loss of libido, erectile dysfunction, difficulty achieving orgasm)¹

Common side effects of tricyclic antidepressants (TCAs)

• Slight blurring of vision
• Dry mouth
• Dizziness
• Drowsiness
• Constipation
• Difficulty passing urine
• Excess sweating (especially at night)
• Weight gain
• Heart rhythm problems (arrhythmias)¹

There are ways to manage some side effects of antidepressants. For instance:

• If you experience headaches, consider taking the dose in the evening and ensure you drink plenty of water.
• If nausea is a problem, taking the medication with or after food may help.
• Using artificial saliva spray can help alleviate a dry mouth.
• However, some side effects, such as sexual dysfunction or heart irregularities, may require a discussion with your prescriber.

It’s important to contact them as soon as you can, so they can monitor your situation and make any necessary adjustments.

Some serious side effects to look out for include:

• Low sodium levels, especially in the elderly. This can lead to fluid build-up and may present with side effects similar to SSRIs such as nausea, headache, and reduced appetite.
• Additionally, muscle pain and confusion can also occur. If this happens the first step is to stop taking the SSRI and contact your prescriber for further guidance.

In more severe cases, symptoms may escalate to disorientation, agitation, psychosis, seizures and even stop you from breathing. In these instances, get help immediately by calling 999.

Serotonin syndrome

Serotonin syndrome is a rare but serious side effect associated with antidepressants, particularly with SSRIs and SNRIs.

It can occur when there is excess serotonin in the body, whether it be due to a high dose, interaction with other medications, or certain herbal treatments e.g. St John’s wort (a common herbal remedy for depression).

Symptoms can appear within hours or days and can include:

• agitation,
• confusion,
• diarrhoea,
• nausea,
• high temperature,
• shivering and sweating,
• muscle twitching,
• or rapid heartbeat.

If you experience these symptoms, stop the medication and seek immediate help from your prescriber, or NHS 111 if out of hours.

Severe symptoms can include irregular heartbeat, seizures and unconsciousness, all of which require immediate help by calling 999.

Suicidal behaviour

Antidepressants have been linked with suicidal thoughts and behaviour, particularly in young individuals with a history of suicidal behaviour.²

Regular reviews and monitoring for suicidal ideation before and during treatment are crucial. If you experience thoughts of self-harm at any time while taking antidepressants, contact your prescriber or, if necessary, go to A&E immediately.

It’s also essential to keep close family and friends informed about your medication, as they can help notice any changes in your behaviour.

Should I avoid anything when on antidepressants?

Make sure your GP is aware of any pre-existing conditions, and they’re noted on your GP record, as some types of antidepressants may not be suitable. Always read the patient information leaflet that comes with your medicine to see if there are any other medicines you should avoid.³

It’s also worth noting that some antidepressants can cause the body’s temperature to rise, therefore making it more difficult to tolerate heat, especially in the summer months.⁴

What should I do if I miss a dose or take extra doses?

It’s important to not miss any doses, as doing so can lead to withdrawal symptoms. Refer to the patient information leaflet for guidance on missed doses for your specific antidepressants. Generally, if a dose is missed, do not double up. Instead, take the next dose at the usual time.

Get in touch with your prescriber or NHS 111 as soon as possible if you have taken more than your prescribed dosage.

Can I stop antidepressants if I feel better?

If you feel better, the antidepressants can’t be stopped immediately. This is because it has taken time for your body’s neurotransmitter to reach a stable level, and discontinuing the medication too soon may risk a relapse.

In most cases, treatment should continue for a minimum of six months after improvement (12 months for elderly individuals). Regular reviews, booked in by your GP or mental health nurse, will take place during this time, to ensure:

• there is no change in treatment,
• confirming whether you are genuinely better and not just responding to the medication.

Healthcare professionals would recommend avoiding the cycle of stopping medication too soon. As this can trigger a return of your symptoms and result in having to restart the stabilisation process again.

Can I stop antidepressants on my own?

It’s not advisable to discontinue antidepressants without consulting your prescriber. Stopping abruptly can lead to withdrawal symptoms and a potential relapse of depression.

They will instead come up with a tapering plan for you to stop the medication gradually after the initial discussion to stop, if suitable.

Are antidepressants addictive?

Antidepressants aren’t addictive. They don’t trigger a euphoric 'high' effect, which is characteristic of addictive substances.

Some individuals may confuse the need to restart antidepressants with medication cravings, as restarting can help alleviate withdrawal symptoms.

What withdrawal symptoms should I expect?

There’s no way to predict if you’ll experience withdrawal symptoms. Some people may have mild symptoms that improve on their own, while others may face more severe symptoms that can last for months.

Continuous communication with your GP or mental health nurse is crucial throughout this process.

When discontinuing antidepressants, a gradual reduction of the medication (referred to as tapering) can help minimise withdrawal symptoms. The tapering process may take several weeks or months, depending on how long you’ve been taking the medication.

Tapering methods can include:

• Reducing the dosage by a specific amount on a set schedule (e.g. 5 mg every week).
• Alternating days of medication, gradually increasing the number of days without it.
• Switching to a different medication or formulation (e.g. liquid formulations allow for smaller, more precise dose reductions, such as 1 mg increments).

These approaches aim to prevent withdrawal symptoms associated with stopping the medication.

Common withdrawal symptoms may include:

• anxiety or restlessness,
• derealisation (feeling that things are not real),
• irritability,
• generally unwell,
• feeling of electric shock in your head,
• stomach problems,
• sleep disturbances such as trouble sleeping or sleepiness,
• sweating.⁵

It’s important to note that tapering plans will not be the same for everyone.

If you find that your tapering plan isn’t effective or if you experience significant withdrawal symptoms, it’s essential to inform your prescriber. They can help reassess your situation and discuss the next steps to better manage the process.

Further resources

• Support groups – NHS
• MIND’s Find local Minds
• Mental Health UK – information and support
• Rethink Mental Illness – who offer local services and peer support groups

Explore more topics around mental health in our mental wellbeing hub.

References

1. Side effects – Antidepressants – NHS
2. Do SSRIs or antidepressants in general increase suicidality? – National Library of Medicine
3. Taking antidepressants with alcohol, food or other medicines – NHS
4. Beating the Heat on Antidepressants – Psychreg
5. Stopping antidepressants – Royal College of Psychiatrists