1.1
Dyspepsia
| Antacids (for example, aluminium hydroxide) | None specifically contraindicated | Any | – |
1.2
Antispasmodics
| Antimuscarinics (for example, hyoscine butylbromide, propantheline bromide) | TCAs (C) (slow gut motility)
Paroxetine (C) (may slow gut motility)
Reboxetine (C) (may slow gut motility) | Any alternative (for example, SSRIs, SNRIs, trazodone) | TCAs, MAOIs and paroxetine may also add to peripheral antimuscarinic effects |
1.3
Peptic ulcer
| H2 antagonists (for example, cimetidine, ranitidine, and so on) | Citalopram/escitalopram (C) (cimetidine inhibits metabolism)
Sertraline (C) (cimetidine inhibits metabolism)
Mirtazapine (C) (cimetidine inhibits metabolism)
Lofepramine (C) (cimetidine inhibits metabolism)
Moclobemide (C) (cimetidine inhibits metabolism) | Any alternative (for example, SSRIs, SNRIs, reboxetine)
Any antidepressant (with ranitidine, nizatidine, and so on) | Cimetidine may inhibit metabolism of many antidepressants Use of SSRIs and SNRIs in active peptic ulcer may increase risk of gastrointestinal bleed |
| Proton pump inhibitors (for example, omeprazole, lansoprazole, and so on) | Citalopram/escitalopram (C) (omeprazole inhibits metabolism) | Any alternative | – |
1.4
Diarrhoea
| Antimotility drugs (for example, codeine, loperamide) | None specifically contraindicated | Any | SSRIs may cause or worsen diarrhoea
SSRIs and SNRIs cause nausea |
1.5
Inflammatory bowel disorders
| Aminosalicylates (for example, mesalazine, olsalazine, balsalazide)
Corticosteroids
Cytokine modulators (for example, infliximab, adalimumab) | None specifically contraindicated | Any | Absorption of antidepressants may be impaired in inflammatory bowel conditions |
1.6
Constipation
| Bulk-forming and stimulant laxatives; faecal softeners | TCAs (A) (slow gut motility)
Paroxetine (A) (may slow gut motility)
Reboxetine (A) (may slow gut motility) | Any alternative (for example, SSRIs).
May increase risk of antidepressant-associated hyponatraemia | Laxatives may be required to treat antidepressant-induced constipation |
2.1–2.2
Heart failure | Cardiac glycosides (digoxin; digitoxin) | St John's wort (A) (reduces digoxin plasma levels)
TCAs (A) (possibly proarrhythmic in cardiac disease)
Venlafaxine (A) (not recommended in those at risk of arrhythmia)
Trazodone (A) (increases digoxin plasma levels) | Any alternative (for example, SSRIs, mirtazapine) | – |
| Thiazide diuretics (bendroflumethiazide, and so on) | Reboxetine (A) (increased risk of hypokalaemia)
MAOIs/TCAs/mirtazapine (C) (increased risk of postural hypotension) | Any alternative (for example, SSRIs) | Avoid lithium – plasma levels increased by thiazides
May increase risk of antidepressant-associated hyponatraemia |
| Loop diuretics (furosemide, bumetanide) | Reboxetine (A) (increased risk of hypocalcaemia)
MAOIs/TCAs (C) (increased risk of postural hypotension) | Any alternative (for example, SSRIs, mirtazapine) | Avoid lithium – plasma levels increased by loop diuretics
May increase risk of antidepressant-associated hyponatraemia |
| Other diuretics (amiloride, eplerenone, and so on) | St John's wort (A) (reduces eplerenone plasma levels) | Any alternative (for example, SSRIs) | May increase risk of antidepressant-associated hyponatraemia |
2.3
Cardiac arrhythmia
| Antiarrhythmics (for example, amiodarone, disopyramide, flecainide, lidocaine, propafenone, and so on) | TCAs (A) (increased risk of arrhythmia)
Citalopram/escitalopram (A) (increases plasma levels of flecainide and propafenone)
Fluoxetine (A) (increases plasma levels of flecainide and propafenone)
Paroxetine (A) (increases plasma levels of flecainide and propafenone)
Duloxetine (A) (increases plasma levels of flecainide)
Venlafaxine (A) (possibility of increased risk of arrhythmia)
Trazodone (C) (possibility of increased risk of arrhythmia)
Reboxetine (C) (may cause hypokalaemia) | Sertraline
Mirtazapine
Moclobemide
Mianserin | All recommended drugs should be used with caution |
2.4–2.5
Hypertension | Beta-adrenoceptor blocking drugs (for example, propranolol, metoprolol, and so on) | TCAs (A) (increased risk of arrhythmia with sotalol)
TCAs (C) (increased risk of postural hypotension)
TCAs (C) (plasma levels increased by labetalol and propranolol)
Citalopram/escitalopram (C) (increases plasma level of metoprolol)
Paroxetine (C) (may increase plasma levels of metoprolol)
Fluvoxamine (C) (increases plasma levels of propranolol)
Mirtazapine (C) (increased risk of postural hypotension)
Venlafaxine (A) (may worsen hypertension)
Duloxetine (A) (may worsen hypertension)
Reboxetine (A) (may worsen hypertension)
Trazodone (C) (increased risk of postural hypotension) | Sertraline | Probably best to avoid all MAOIs because of the risk of hypertensive crisis |
| Vasodilator drugs (for example, diazoxide, hydralazine, prazosin, doxazosin) | TCAs (C) (increased risk of postural hypertension)
Mirtazapine (C) (increased risk of postural hypertension)
Venlafaxine (A) (may worsen hypertension)
Duloxetine (A) (may worsen hypertension)
Reboxetine (A) (may worsen hypertension) | Any alternative (for example, SSRIs) | Probably best to avoid all MAOIs because of the risk of hypertensive crisis
Paroxetine and fluoxetine may inhibit metabolism of doxazosin |
| Centrally-acting antihypertensives (for example, methyldopa, clonidine, and so on) | TCAs (A) (antagonise effects of clonidine)
Mirtazapine (C) (increased risk of postural hypertension)
Venlafaxine (A) (may worsen hypertension)
Duloxetine (A) (may worsen hypertension)
Reboxetine (A) (may worsen hypertension)
Trazodone (C) (increased risk of postural hypotension) | Any alternative (for example, SSRIs) | Probably best to avoid all MAOIs because of the risk of hypertensive crisis
Mirtazapine and trazodone may antagonise effects of clonidine |
| ACE inhibitors; angiotensin-II antagonists; renin inhibitors (for example, captopril, enalapril; losartan; aliskiren) | TCAs (C) (increased risk of postural hypotension)
Mirtazapine (C) (increased risk of postural hypotension)
MAOIs (A) (may enhance hypotensive effects of ACE inhibitors and angiotensin antagonists)
Venlafaxine (A) (may worsen hypertension)
Duloxetine (A) (may worsen hypertension)
Reboxetine (A) (may worsen hypertension) | Any alternative (for example, SSRIs) | Avoid lithium – plasma levels increased by ACE inhibitors |
| Calcium channel antagonists (for example, nifedipine, verapamil) | TCAs (C) (increased risk of postural hypotension)
Mirtazapine (C) (increased risk of postural hypotension)
Venlafaxine (A) (may worsen hypertension)
Duloxetine (A) (may worsen hypertension)
Reboxetine (A) (may worsen hypertension)
Trazodone (C) (increased risk of postural hypotension) | Any alternative (for example, SSRIs) | Avoid lithium – diltiazem and verapamil may precipitate neurotoxicity |
2.6
Angina
| Nitrates (for example, GTN, isosorbide nononitrate) | TCAs (C) (dry mouth may reduce absorption of sub-lingual tablets)
MAOIs (A) (enhanced hypotensive effects) | Any alternative (for example, SSRIs) | Paroxetine has mild anticholinergic properties |
2.8–2.9
Conditions requiring anticoagulation | Parenteral anticoagulants (for example, heparin, low molecular-weight heparin) | SSRIs (A) (probable increased risk of bleeding)
Venlafaxine (A) (probable increased risk of bleeding)
Duloxetine (A) (probable increased risk of bleeding) | Any alternative (for example, trazodone, reboxetine, TCAs) | – |
| Oral anticoagulants (warfarin, phenindione) | SSRIs (A) (enhanced anticoagulant effect)
TCAs (A) (enhanced or reduced anticoagulant effect)
Mirtazapine (A) (enhanced anticoagulant effect)
St John's wort (A) (reduced warfarin plasma levels)
Venlafaxine (C) (possibility of enhanced anticoagulant effect)
Duloxetine (C) (possibility of enhanced anticoagulant effect) | Reboxetine (C)
Trazodone (C)
Mianserin (C) | Fluvoxamine and fluoxetine inhibit warfarin metabolism
Anticoagulant effect may be enhanced without change in INR |
2.12
Dyslipidaemia
| Bile acid sequestrants (for example, colestipol, colestyramine) | None specifically contraindicated | Any | – |
| Ezetimibe | None specifically contraindicated | Any | – |
| Fibrates (for example, bezafibrate) | None specifically contraindicated | Any | Probably best to avoid MAOIs with bezafibrate – risk of hepatotoxicity |
| Statins (for example, atorvastatin, simvastatin) | St John's wort (A) (reduces effect of simvastatin) | Any alternative (for example, SSRIs, TCAs, others) | – |
| Omega-3 fatty acids (for example, MaxEPA, Omacor) | None specifically contraindicated | Any | Omega-3 fatty acids may have antidepressant effects |
3.1–3.3
Asthma/COPD | Inhaled bronchodilators (for example, salbutamol, ipratropium) | None specifically contraindicated | Any | – |
| Theophylline | Fluvoxamine (A) (inhibits theophylline metabolism)
St John's wort (A) (increases theophylline metabolism) | Any alternative (for example, other SSRIs) | – |
| Corticosteroids (for example, predrisolone, beclomethasone) | None specifically contraindicated | Any | – |
| Leukotriene antagonists (for example, montelukast) | None specifically contraindicated | Any | – |
3.4
Allergy
| Antihistamines – sedating (for example, chlorphenamine, hydroxyzine, promethazine) | TCAs (C) (increased sedation and anticholinergic effects)
Trazodone (C) (increased sedation)
Mirtazapine (C) (increased sedation)
Phenelzine (C) (increased sedation and anticholinergic effects)
SSRIs (C) (effect antagonised by cyproheptadine) | Any alternative (SSRIs, reboxetine) | Probably best to avoid use of cyproheptadine with serotonergic antidepressants |
| Antihistamines – non-sedating (for example, cetirizine, loratidine, mizolastine) | TCAs (C) (possibility of increased sedative effects)
Trazodone (C) (possibility of increased sedative effects)
Mirtazapine (C) (possibility of increased sedative effects) | Any alternative (for example, SSRIs, reboxetine) | Avoid use of mizolastine with TCAs and venlafaxine |
| Omalizumab | None specifically contraindicated | Any | – |
| Adrenaline | TCAs (A) (risk of hypertension and arrhythmia) | Any | Where adrenaline is required in a patient on TCAs, close monitoring is essential |
| Oral nasal decongestants (for example, pseudoephedrine) | MAOIs (A) (risk of hypertensive crisis)
TCAs (C) (manufacturer advises caution) | Any alternative | – |
4.1.1
Insomnia
| Hypnotics (for example, temazepam, Z-drugs, chloralhydrate, promethazine) | TCAs (C) (increased sedation)
Mirtazapine (C) (increased sedation)
Trazodone (C) (increased sedation) | Any alternative (for example, SSRIs [C], SNRIs, reboxetine) | Fluvoxamine, paroxetine and fluoxetine may prolong the action of some benzodiazepines
Sertraline may increase sedative effects of Zolpidem |
4.1.2–4.1.3
Anxiety | Anxiolytics (for example, benzodiazepines, buspirone, meprobamate, barbiturates) | TCAs (C) (increased sedation)
Mirtazapine (C) (increased sedation)
Trazodone (C) (increased sedation)
MAOIs (A) (avoid with buspirone only) | Any alternative (for example, SSRIs [C], SNRIs, reboxetine) | Fluvoxamine, paroxetine and fluoxetine may prolong the action of some benzodiazepines
St John's wort may reduce the effect of some benzodiazepines |
4.2
Psychosis
| Antipsychotics (for example, chlorpromazine, haloperidol, clozapine, olanzapine) | TCAs (C) (increased risk of hypotension, sedation and arrhythmia)
Mirtazapine (C) (increased risk of sedation)
Trazodone (C) (increased risk of sedation and hypotension)
Paroxetine (C) (increases clozapine plasma levels)
Fluoxetine (C) (increased clozapine plasma levels)
Fluvoxamine (A) (substantially increased clozapine plasma levels)
Venlafaxine (C) (possibility of increased risk of arrhythmia) | Any alternative (for example, citalopram, reboxetine) | Complex interactions with individual drugs – consult specialist before initiating a new antidepressant |
4.2.3
Bipolar disorder
| Mood stabilisers (for example, lithium, valproate, carbamazepine) | SSRIs (C) (increased risk of central nervous system effects)
Venlafaxine (C) (increased risk of serotonergic effects; possible risk of increased lithium levels)
TCAs (C) (increased risk of serotonergic effects; possible increased risk of lithium toxicity)
St John's wort (A) (reduced plasma levels of carbamazepine) | Any alternative (for example, mirtazapine, reboxetine, duloxetine) | SSRIs and TCAs are widely used alongside lithium – adverse interactions are rare
Carbamazepine is a potent enzyme inducer and reduces plasma levels of many TCAs and other antidepressants |
4.4
ADHD
| Stimulants (for example, dexamfetamine, methylphenidate, atomoxetine, modafinil) | TCAs (A) (increased risk of arrhythmia)
MAOIs (A) (risk of hypertensive crisis)
Moclobemide (A) (risk of hypertensive crisis)
Fluoxetine (A) (increased plasma levels of atomoxetine)
Paroxetine (A) (increased plasma levels of atomoxetine)
Mirtazapine (C) (manufacturer advises caution with atomoxetine)
Reboxetine (C) (manufacturer advises caution with atomoxetine) | Any alternative (for example, citalopram, sertraline, reboxetine [C], mirtazapine [C]) | All antidepressants may increase risk of convulsions when given with atomoxetine
SSRIs/SNRIs may increase risk of serotonin syndrome with dexamfetamine |
4.5
Obesity
| Orlistat | None specifically contraindicated | Any | Decreased gut transit time may affect absorption of some drugs |
| Centrally acting appetite suppressants (for example, sibutramine) | All antidepressants (A) (increased risk of central nervous system toxicity with sibutramine) | None | Avoid co-prescription of antidepressants with sibutramine |
4.6
Nausea and vertigo
| Antihistamines (for example, cinnarizine, promethazine) | TCAs (C) (increased risk of sedation)
Trazodone (C) (increased risk of sedation)
Mirtazapine (C) (increased risk of sedation)
MAOIs (A) (contraindicated with promethazine) | Any alternative (for example, SSRIs, venlafaxine, reboxetine) | SSRIs, venlafaxine, duloxetine frequently cause or worsen nausea and vomiting |
| Phenothiazines (for example, prochlorperazine) | TCAs (C)
(increased risk of sedation and possibly arrhythmia)
Mirtazapine (C)
(increased risk of sedation)
Trazodone (C)
(increased risk of sedation) | Any alternative (for example, SSRIs, SNRIs, reboxetine) |
| Domperidone and metoclopramide | None specifically contraindicated | Any |
| 5-HT3 receptor antagonists (for example, ondansetron) | None specifically contraindicated | Any |
| Nabilone | TCAs (C) (increased risk of sedation)
Mirtazapine (C) (increased risk of sedation)
Trazodone (C) (increased risk of sedation) | Any alternative (for example, SSRIs, SNRIs, reboxetine) |
| Hyoscine | TCAs (C) (increased risk of sedation and antimuscarinic effects)
Mirtazapine (C) (increased risk of sedation)
Trazodone (C) (increased risk of sedation) | Any alternative (for example, SSRIs, SNRIs, reboxetine) |
4.7.1–4.7.2
Pain | Aspirin/paracetamol (with or without mild opiates) | SSRIs (C) (increased risk of bleeding with aspirin)
Venlafaxine (C) (increased risk of bleeding with aspirin) | Any alternative (for example, TCAs, mirtazapine, trazodone) | |
| Opioids | TCAs (C) (increased risk of sedation and constipation)
Trazodone (C) (increased risk of sedation)
Mirtazapine (C) (increased risk of sedation)
MAOIs (A) (increased risk of central nervous system [CNS] excitation and depression)
Moclobemide (A) (increased risk of CNS excitation and depression)
SSRIs (C) (increased risk of CNS toxicity with tramadol, pethidine and oxycodone)
Fluvoxamine (A) (increased plasma levels of methadone)
Duloxetine (C) (increased risk of serotonergic effects with tramadol and pethidine) | Any alternative (for example, SSRIs (C), mirtazapine (C), reboxetine) | |
4.7.4
Migraine
| 5HT1 agonists (for example, sumatriptan, zolmitriptan) | SSRIs (A) (increased risk of CNS toxicity and serotonergic effects)
Duloxetine (A) (increased risk of serotonergic effects)
Venlafaxine (A) (increased risk of serotonergic effects)
MAOIs (A) (increased risk of CNS toxicity)
Moclobemide (A) (increased risk of CNS toxicity) | Any alternative (for example, TCAs, trazodone, mirtazapine) | Probably best to avoid clomipramine |
| Ergot alkaloids (for example, ergotamine) | Reboxetine (A) (increased risk of hypertension)
SSRIs (C) (increased risk of serotonin syndrome) | Any alternative | |
Migraine prophylactic agents
(for example, pizotifen, clonidine) | Reboxetine (A) (increased risk of hypertension with methysergide)
TCAs/reboxetine/trazodone/mirtazapine (C) (may antagonise effects of clonidine) | Any alternative (for example, SSRIs) | Some manufacturers suggest avoiding co-administration of MAOIs and TCAs with some alpha2 agonists (but not clonidine) |
4.8
Epilepsy
| Anticonvulsants (for example, valproate, carbamazepine) | Complex interactions – seek specialist advice |
4.9.1–4.9.2
Parkinson's disease | Dopamine agonists (for example, bromocriptine, pramipexole) | None specifically contraindicated | Any | Dopamine agonists have some antidepressant properties
SSRIs, particularly paroxetine, may worsen symptoms of Parkinson's disease
Selegiline also has antidepressant activity |
| Levodopa (for example, sinemet, madopar) | MAOIs (A) (increased risk of hypertension)
Moclobemide (C) (increased risk of adverse effects) | Any alternative (for example, SSRIs, SNRIs, TCAs, trazodone, and so on) |
| MAO-B inhibitors (for example, selegiline, rasagiline) | SSRIs (A) (increased risk of CNS excitation and hypertension)
TCAs (A) (increased risk of CNS excitation)
MAOIs (A) (increased risk of hypotension)
Moclobemide (A) (increased risk of CNS excitation)
Venlafaxine (A) (increased risk of CNS excitation)
Duloxetine (A) (increased risk of CNS excitation) | Trazodone, reboxetine, mirtazapine |
| COMT inhibitors (entacapone, tolcapone) | MAOIs (A) (increased risk of hypertension)
TCAs (C) (manufacturer advises caution)
SSRIs (C) (manufacturer advises caution)
Moclobemide (C) (manufacturer advises caution)
Venlafaxine (C) (manufacturer advises caution)
Duloxetine (C) (manufacturer advises caution) | SSRIs, trazodone (with caution) |
| Amantadine | None specifically contraindicated | Any |
| Antimuscarinic drugs (for example, procyclidine, benzatropine) | TCAs (C) (increased antimuscarinic effects)
MAOIs (C) (increased antimuscarinic effects)
Paroxetine (C) (increased plasma levels of procyclidine) | Any alternative (for example, SSRIs, mirtazapine, trazodone) |
4.9.3
Tremor, chorea, tics and related disorders
| Haloperidol | TCAs (A) (increased risk of arrhythmia) | Any alternative (for example, SSRIs, mirtazapine) | |
| Riluzole | None specifically contraindicated | Any | May be best to avoid antidepressants associated with nausea (SSRIs, venlafaxine, duloxetine) and neutropenia (mianserin) |
| Tetrabenazine | MAOIs (A) (increased risk of central nervous system excitation and hypertension) | Any alternative | Tetrabenazine is a well known precipitant of depression
Paroxetine/fluoxetine may inhibit metabolism of tetrabenazine |
4.10
Alcohol dependence
| Acamprosate | None specifically contraindicated | Any alternative | |
| Disulfiram | TCAs (A)
(increased plasma concentration and increased reaction to alcohol) | Any alternative | All antidepressants should be used with caution |
4.10
Smoking
| Bupropion | TCAs (A) (increased risk of seizures)
MAOIs (A) (manufacturer advises avoiding concomitant use)
Citalopram (C) (possibility of increased plasma levels) | Any alternative (for example, SSRIs) | Bupropion is an antidepressant; has been safely used at the same time as SSRIs
Probably inhibits metabolism of all SSRIs |
| Nicotine | None specifically contraindicated | Any alternative | Note that smoking induces CYP1A2. Plasma levels of fluvoxamine and some other antidepressants may be decreased by smoking. Increases are to be expected on cessation |
| Varenicline | None specifically contraindicated | Any alternative | Note that mood changes, depression and suicidal ideation have been reported |
4.10
Opioid dependence
| Buprenorphine | TCAs (C) (increased risk of sedation and constipation)
Trazodone (C) (increased risk of sedation)
Mirtazapine (C) (increased risk of sedation) | Any alternative (for example, any SSRIs) | Manufacturer advises caution with MAOIs |
| Methadone | Fluvoxamine (A) (increased levels of methadone)
MAOIs (A) (contraindicated by manufacturer) | Any alternative | Sertraline, paroxetine and fluoxetine may increase methadone plasma levels – caution |
| Lofexidine | TCAs (A) (increased risk of arrhythmia)
Mirtazapine (C) (may antagonise effects of lofexidine) | Any alternative | – |
| Naltrexone | None specifically contraindicated | Any | – |
4.11
Dementia
| Acetylcholinesterase inhibitors
(for example, donepezil) | TCAs (A) (antagonises effect of anti-dementia drugs)
MAOIs (A) (antagonises effect of anti-dementia drugs)
Paroxetine (C) (increased plasma levels of galantamine)
Fluoxetine (C) (may increase plasma levels of galantamine) | Any alternative (for example, SSRIs, trazodone, mirtazapine) | Antimuscarinic effects of some antidepressants directly antagonise effects of cholinesterase inhibitors
Probably best to avoid antimuscarinic antidepressants with memantine |
| Memantine | None specifically contraindicated | Any |
5.1
Infection (bacterial)
| Penicillins (for example, amoxicillin, phenoxymethylpenicillin, flucloxacillin) | None specifically contraindicated | Any | – |
| Cephalosporins (for example, cefadroxil, cefalexin) | None specifically contraindicated | Any | – |
| Tetracyclines (for example, doxycycline, oxytetracycline) | None specifically contraindicated | Any | – |
| Macrolides (for example, erythromycin, clairthromycin) | TCAs (A) (increased risk of QT prolongation)
Reboxetine (A) (manufacturer suggests avoid concomitant use)
Mirtazapine (C) (plasma levels may be increased)
Trazodone (C) (plasma levels may be increased by erythromycin)
Venlafaxine (C) (plasma levels may be increased | Any alternative (for example, SSRIs) | Erythromycin and fluvoxamine may inhibit each other's metabolism – avoid |
| Clindamycin | None specifically contraindicated | Any | – |
| Sulphonamides (co-trimoxazole) | Mianserin (C) (increased risk of blood dyscrasia) | Any alternative | – |
| Anti-tuberculosis drugs (for example, isoniazid, rifampicin, ethambutol) | TCAs (C) (increased risk of seizures with cycloserine; plasma levels reduced by rifampicin) | Any alternative (for example, SSRIs, mirtazapine, trazodone) | Rifamycins potent enzyme inducers. Caution with all antidepressants |
| Metronidazole and tinidazole | None specifically contraindicated | Any | – |
| Quinolones (for example, ciprofloxacin, norfloxacin) | TCAs (A) (increased risk of arrhythmia)
Duloxetine (C) (metabolism inhibited by ciprofloxacin) | Any alternative (for example, SSRI, mirtazapine) | – |
| Drugs for urinary tract infection (for example, nitrofurantoin, methenamine) | None specifically contraindicated | Any | – |
5.2
Infection (fungal)
| Antifungal drugs (for example, fluconazole, itraconazole, voriconazole, ketoconazole, terbinafine) | Reboxetine (A) (manufacturer advises avoiding concomitant use of imidazoles and triazoles)
Mirtazapine (C) (plasma level increased by ketoconazole)
St John's wort (A) (reduces plasma levels of voriconazole)
TCAs (C) (plasma levels increased by terbinafine) | Any alternative (for example, SSRIs) | Ketoconazole is a CYP3A4 inhibitor. May increase levels of mirtazapine, reboxetine, venlafaxine, trazodone and some TCAs
Terbinafine inhibits CYP2D6. May increase levels of SSRIs and TCAs |
5.3
Infection (viral)
| Drugs for HIV (for example, zidovudine, indinavir, amprenavir, darunavir, ritonavir, efavirenx) | SSRIs (C) (plasma levels reduced by amprenavir, darunavir, ritonavir [may also increase levels] and efavirenz)
TCAs (C) (possibility of increased plasma levels/side effects with amprenavir and ritonavir)
Trazodone (C) (increased side effects with ritonavir)
Venlafaxine (A) (decreased plasma levels of indinavir) | Any alternative (for example, mirtazapine, reboxetine) | Complex interactions. Seek specialist advice where possible
SSRIs recommended by specialist guidelines |
| Drugs for herpes simplex and varicella (for example, acyclovir) | None specifically contraindicated | Any | – |
| Drugs for cytomegalovirus (for example, ganciclovir) | None specifically contraindicated | Any | – |
| Drugs for hepatitis B (for example, entecavir) | None specifically contraindicated | Any | – |
| Drugs for influenza (for example, oseltamivir, zanamivir) | None specifically contraindicated | Any | – |
5.4
Infection (protozoal)
| Antimalarials (for example, chloroquine, mefloquine, quinine, artemether, lumefantrine) | None specifically contraindicated (except with artemether/lumefantrine [Riamet]) | Any – but see comment | Avoid all antidepressants with artemether/ lumefantrine (Riamet)
Quinine and mefloquine should not be given at the same time as TCAs (risk of arrhythmias)
Quinine inhibits CYP2D6. May increase levels of SSRIs and TCAs |
| Amoebicides (for example, metronidiazole, tinidazole) | None specifically contraindicated | Any | – |
5.5
Infection (helmintic)
| Antihelmintics (for example, mebenazdole, piperazine) | None specifically contraindicated | Any | – |
6.1
Diabetes
| Insulin | SSRIs (C) (changes in blood glucose reported)
TCAs (C) (tachycardia/hypotension may mimic hyperglycaemia)
MAOIs (A) (hypoglycaemic effects enhanced) | Any alternative (for example, mirtazapine, SNRIs, reboxetine) | Mirtazapine may cause weight gain |
Oral hypoglycaemics
Sulphonylureas
(for example, glibenclamide, glipizide)
Biguanides
(metformin)
Others
(for example, exenatide, pioglitazone, rosiglitazone) | SSRIs (C) (changes in blood glucose reported)
TCAs (C) (tachycardia/hypotension may mimic hypoglycaemia)
MAOIs (C) (hypoglycaemic effects enhanced) | Any alternative (for example, mirtazapine, SNRIs, reboxetine) | Mirtazapine may cause weight gain |
6.2
Thyroid disease
| Thyroxine; liothyronine | None specifically contraindicated | Any | Thyroid hormones enhance antidepressant effects
Theoretical risk of arrhythmia with TCAs - caution |
Antithyroid drugs
(for example, carbimazole) | Mianserin
(possibility of increased risk of blood dyscrasia) | Any alternative | – |
6.3.2
Glucocorticoid therapy
| Corticosteroids
(for example, prednisolone) | None specifically contraindicated (but see comments)
SSRIs/venlafaxine/duloxetine (C) (possibility of increased risk of upper gastrointestinal bleeding) | Any alternative (for example, reboxetine, mirtazapine, trazodone) | Corticosteroids associated with euphoria, mood changes, depression and suicide |
6.4
Menopause
| HRT
(various preparations) | None specifically contraindicated | Any | – |
6.4
Testosterone-related syndromes
| Testosterone | None specifically contraindicated | Any | – |
Anti-androgens
(cyproterone, dutasteride) | None specifically contraindicated | Any | – |
| Anabolic steroids (for example, nandrolone) | None specifically contraindicated | Any | – |
6.5.1
Infertility
| Clomifene | None specifically contraindicated | Any | – |
Gonadotrophins
(for example, follitropin) | None specifically contraindicated | Any | – |
6.5.1
Growth failure
| Human growth hormone
(for example, somatropin) | None specifically contraindicated | Any | – |
6.5.1
Agromegaly
| Growth hormone antagonists
(for example, pegvisomant) | None specifically contraindicated | Any | – |
6.5.2
Diabetes insipidus
| ADH (for example, vasopressin, desmopressin) | None specifically contraindicated | Any | All antidepressants linked to syndrome of inappropriate antidiuretic hormone hypersecretion (SIADH) |
6.5
SIADH
| Demeclocycline | None specifically contraindicated | Any | All antidepressants associated with SIADH |
6.6.2
Osteoporosis
| Bisphosphonates
(for example, disodium, elidronate, sodium clodronate) | None specifically contraindicated | Any | – |
6.7.2
Endometriosis
| Danazol, gestrinone | None specifically contraindicated | Any | Danazol has enzyme-inhibiting properties |
Gonadorelin amalogues
(for example, goserelin) | None specifically contraindicated | Any | – |
6.7.2
Female infertility
| LHRH antagonists
(for example, cetrorelix, ganirelix) | None specifically contraindicated | Any | May induce mood changes |
6.7.3
Cushing's syndrome
| Metyrapone, trilostane | None specifically contraindicated | Any | Very high prevalence of depression in Cushing's syndrome |
7.3
Contraception
| Oral contraceptives
(for example, combined oral/progesterone only) | TCAs (C) (possibility of increased plasma levels and antagonism of antidepressant effects)
St John's wort (A) (reduced contraceptive effect) | Any alternative
(for example, SSRIs, mirtazapine, reboxetine, trazodone) | Oestrogens have depressogenic effects |
7.4.1
Urinary retention
| Alpha-blockers
(for example, doxazosin, indoramin) | See 2.4/2.5 | See 2.4/2.5 | – |
7.4.2
Urinary frequency/ incontinence
| Antimuscarinics
(for example, oxybutynin propiverine) | TCAs (C) (increased antimuscarinic effects)
Paroxetine (C) (increased antimuscarinic effects) | Any alternative
(for example, SSRIs, mirtazapine, reboxetine, trazodone) | – |
7.4.5
Erectile dysfunction
| Phosphodiesterase inhibitors
(for example, sildenafil) | TCAs (C) (possible increased hypotensive effects)
Trazodone (C) (possible increased hypotensive effects) | Any alternative
(for example, SSRIs, SNRIs, mirtazapine, reboxetine) | Inhibitors of CYP3A4 (paroxetine, fluoxetine) may increase plasma levels of phosphodiesterase inhibitors. Use with caution |
8.1–8.2
Malignant diseases | Cytotoxic drugs
Alkylating agents
(for example, chlormabucil, cyclophosphamide)
Anthracyclines
(for example, daunorubicin, doxorubicin)
Antimetabolites
(for example, methotrexate)
Vinca alkaloids
(for example, etoposide, vincristine)
Platinum compounds
(for example, cisplatin, carboplatin) | Mianserin (A) (possible increased risk of bone marrow suppression) | Any alternative | – |
Protein kinase inhibitors
(for example, imatinib, nilotinib) | Mianserin (A) (possible increased risk of bone marrow suppression)
TCAs (A) (possibly increased risk of QT prolongation) | Any alternative
(for example, SSRIs, mirtazapine, trazodone) | Nilotinib is an inhibitor of CYP3A4 and 2D6. Caution with all antidepressants |
Taxanes
(for example, paclitaxel) | Mianserin (A)
(possibility of increased risk of bone marrow suppression) | Any alternative | – |
Topoisomerase inhibitors
(for example, irinotecan) | Mianserin (A)
(possibility of increased risk of bone marrow suppression) | Any alterative | – |
| Trastuzumab | Mianserin (A)
(possibility of increased risk of bone marrow suppression)
TCAs (A)
(possibility of increased risk of arrhythmia) | Any alternative | – |
8.2.1
Organ transplantation
| Antiproliferative immunosuppressants (for example, azathioprine, mycophenolate) | Mianserin (A)
(possibility of increased risk of bone marrow suppression) | Any alternative | – |
| Other immunosuppressants (for example, ciclosporin, tacrolimus) | Mianserin (A) (possibility of increased risk of bone marrow suppression)
St John's wort (A) (reduced plasma levels of ciclosporin and tacrolimus) | Any alternative
(for example, SSRIs, mirtazapine, trazodone) | Paroxetine and fluoxetine inhibit CYP3A4 and may increase ciclosporin and tacrolimus levels |
8.2.3
Lymphoma
| Rituximab and alemtuzumab | Mianserin (A) (possibility of increased risk of bone marrow suppression)
TCAs (A) (possibility of increased risk of hypotension and arrhythmia) | Any alternative
(for example, SSRIs, SNRIs, mirtazapine, trazodone) | – |
8.2.4
Hepatitis/multiple sclerosis
| Interferon alfa, interferon beta, glatiramer, natalizumab | Mianserin (A) (increased risk of bone marrow suppression) | Any alternative | Depression and suicidal ideation well established adverse effects of interferons |
8.3.4
Breast cancer
| Oestrogenantagonists
(tamoxifen)
Aromatase inhibitors
(for example, anastrozole, letrozole) | None specifically contraindicated | Any | – |
8.3.4
Prostate cancer
| Gonadorelin antagonists
(for example, goserelin)
Anti-androgens (for example, cyproterone) | None specifically contraindicated | Any | May induce mood changes |
9.1
Iron deficiency
| Ferrous sulphate, ferrous fumarate | TCAs (C) (worsens constipation) | Any alternative | – |
9.1
Megaloblastic anaemias
| Hydroxocobalamin, folic acid | None specifically contraindicated | Any | – |
9.1
Renal anaemias
| Epoetin | Venlafaxine (C) (increased risk of hypertension)
Duloxetine (C) (increased risk of hypertension)
Reboxetine (C) (increased risk of hypertension) | Any alternative (for example, SSRIs, mirtazapine, TCAs) | – |
9.6
Vitamin deficiency
| Vitamins
(for example, retinol, thiamine, ascorbic acid, ergocalciterol, tocopherols) | None specifically contraindicated | Any | – |
10.1.1
Musculoskeletal and joint disease
| NSAIDs
(for example, ibuprofen, naproxen, coxibs) | SSRIs (A) (increased risk of bleeding)
SNRIs (A) (increased risk of bleeding) | Any alternative (for example, mirtazapine, reboxetine, TCAs) | – |
10.1.3
Rheumatoid arthritis
| Disease-modifying agents
(for example, gold, penicillin, chloroquine) | Mianserin (A) (increased risk of blood toxicity)
TCAs (A) (increased risk of arrhythmia with chloroquine/hydroxychloroquine) | Any alternative (for example, SSRIs, SNRIs, mirtazapine) | – |
10.1.3
Drugs affecting immune response in rheumatoid arthritis
| Methotrexate, azathioprine, ciclosporin, cytokine modulators, tumour necrosis factor-alpha inhibitors | Mianserin (A) (increased risk of blood dyscrasia)
St John's wort (A) (reduces plasma levels of ciclosporin) | Any alternative | – |
10.1.4
Gout and hyperuricaemia
| Colchicine, allopurinol, sulfinpyrazone probenecid (for NSAIDs see above) | Mianserin (A) (increased risk of blood dyscrasia with allopurinol and sulfinpyrazone) | Any alternative | – |
10.2.1
Myasthaenia gravis
| Anticholinesterases
(for example, neostigmine, pyridostigmine) | None specifically contraindicated | Any | TCAs may ameliorate some parasympathetic adverse effects |
10.2.2
Muscle spasm or spasticity
| Baclofen, dantrolene, and so on | Fluvoxamine (A) (increases plasma levels of tizanidine)
TCAs (A) (effect of baclofen enhanced) | Any alternative | – |
11.6
Glaucoma
| Carbonic anhydrase inhibitors
(for example, acetazolamide) | None specifically contraindicated | Any | Many antimuscarinic antidepressants are contraindicated in glaucoma |
14.4
Infectious disease prevention
| Vaccines | None specifically contraindicated | Any | – |
