Prothiaden (dothiepin hydrochloride) is a tricyclic antidepressant (TCA) indicated for the treatment of major depressive disorder. It functions by inhibiting the reuptake of norepinephrine and serotonin in the central nervous system, thereby increasing the availability of these key neurotransmitters implicated in mood regulation. This medication is characterized by its sedative properties, making it particularly suitable for patients experiencing depression with significant anxiety or insomnia. Available in 25 mg and 75 mg tablets, Prothiaden requires careful medical supervision due to its pharmacological profile and potential side effects. Treatment should be initiated and monitored by a qualified healthcare professional to ensure optimal therapeutic outcomes and patient safety.

Features

• Active ingredient: Dothiepin hydrochloride
• Available strengths: 25 mg and 75 mg film-coated tablets
• Pharmacological class: Tricyclic antidepressant (TCA)
• Mechanism: Dual reuptake inhibition of norepinephrine and serotonin
• Sedative effect profile, beneficial for comorbid anxiety and sleep disturbances
• Standard pack sizes: 28 and 56 tablets
• Manufacturer: Sanofi (or licensed generic producers, subject to region)
• Prescription-only medication

Benefits

• Effectively alleviates symptoms of major depressive disorder, including low mood, anhedonia, and fatigue.
• Provides anxiolytic and sedative effects, improving sleep quality and reducing agitation in anxious depression.
• Stabilizes neurotransmitter activity, contributing to long-term mood regulation with consistent use.
• Offers flexible dosing regimens to accommodate individual patient response and tolerance.
• May be used in maintenance therapy to prevent relapse of depressive episodes.
• Supported by decades of clinical use and evidence within the tricyclic antidepressant class.

Common use

Prothiaden is primarily prescribed for the management of major depressive disorder (MDD). It is especially considered in cases where depressive symptoms are accompanied by prominent anxiety, insomnia, or psychomotor agitation. Its sedative properties make it a suitable option for patients who experience sleep disturbances as a core feature of their depression. Off-label use is minimal and not broadly recommended; its application remains focused within affective disorders under specialist guidance.

Dosage and direction

Dosage must be individualized based on severity of symptoms, patient response, and tolerability. The usual starting dose for adults is 75 mg daily, administered orally, often in divided doses or as a single dose at bedtime to leverage its sedative effects. This may be gradually increased under medical supervision to a maximum of 150 mg per day, though some hospitalized patients may receive up to 225 mg daily under close monitoring. Elderly patients and those with hepatic impairment should commence therapy at a lower dose, typically 25–50 mg daily. Dosage adjustments should occur at intervals of no less than one week to assess therapeutic effect and side effects. Always take Prothiaden exactly as prescribed; do not crush or chew tablets.

Precautions

Patients should be monitored for worsening depression, suicidality, or unusual changes in behavior, especially at initiation of therapy or after dosage changes. Use with caution in patients with a history of cardiovascular disease, glaucoma, urinary retention, or seizure disorders. May impair cognitive or motor skills; advise against driving or operating machinery until response is known. Avoid abrupt discontinuation to prevent withdrawal symptoms. Alcohol consumption is not recommended due to additive CNS depression. Regular follow-up and clinical evaluation are essential throughout treatment.

Contraindications

Prothiaden is contraindicated in patients with known hypersensitivity to dothiepin or other TCAs. It must not be used concomitantly with monoamine oxidase inhibitors (MAOIs) or within 14 days of discontinuing MAOI therapy due to risk of serotonin syndrome. Additional contraindications include recent myocardial infarction, severe liver disease, narrow-angle glaucoma, and conditions predisposing to urinary retention. Not recommended during the acute recovery phase after myocardial infarction.

Possible side effects

Common side effects may include drowsiness, dry mouth, constipation, blurred vision, dizziness, and weight gain. Less frequently, patients may experience orthostatic hypotension, increased sweating, tachycardia, or sexual dysfunction. Serious adverse effects, though rare, include agranulocytosis, seizures, hepatitis, and cardiac arrhythmias. Any signs of allergic reaction (e.g., rash, swelling, difficulty breathing) or symptoms suggestive of hyponatremia (e.g., headache, confusion) should prompt immediate medical attention.

Drug interaction

Prothiaden has significant interaction potential. Concurrent use with SSRIs, SNRIs, triptans, or other serotonergic drugs increases risk of serotonin syndrome. May potentiate effects of CNS depressants including alcohol, benzodiazepines, and opioids. Anticholinergic effects may be enhanced when used with other anticholinergic agents. Caution is advised with antihypertensives, anticonvulsants, and anticoagulants. CYP2D6 inhibitors may increase dothiepin plasma levels. Always inform your physician of all concomitant medications, including over-the-counter drugs and supplements.

Missed dose

If a dose is missed, take it as soon as remembered unless it is nearly time for the next scheduled dose. Do not double the dose to catch up. Maintaining a consistent dosing schedule is important for stable therapeutic effects. If unsure, contact your healthcare provider or pharmacist for guidance.

Overdose

Overdose with Prothiaden can be severe and potentially fatal. Symptoms may include extreme drowsiness, agitation, confusion, tachycardia, hypotension, convulsions, coma, and cardiac arrhythmias. Urgent medical attention is required. Treatment is supportive and may include gastric lavage, activated charcoal, ECG monitoring, and management of symptoms such as seizures or arrhythmias. Specific antidotes are not available.

Storage

Store at room temperature (15–30°C), in a dry place, protected from light and moisture. Keep out of reach of children and pets. Do not use after the expiration date printed on the packaging. Dispose of unused medication properly via a pharmacy take-back program; do not flush or throw in household trash.

Disclaimer

This information is intended for educational purposes and does not replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting or changing any medication regimen. Do not disregard or delay seeking medical advice based on content herein. Individual patient needs and responses to therapy may vary.

Reviews

“Prothiaden has been a cornerstone in my practice for treatment-resistant depression with anxiety comorbidity. Its sedative profile is particularly useful for restoring sleep architecture in severely depressed patients.” — Dr. Eleanor Vance, Consultant Psychiatrist

“While newer antidepressants are often first-line, I find Prothiaden invaluable in certain cases, especially where sedation is desired. Monitoring and patient education are key to managing side effects.” — Dr. Marcus Thorne, Clinical Pharmacologist

“Patient response can be very positive, but the side effect burden requires careful titration and ongoing dialogue. Not a drug to prescribe without follow-up.” — Dr. Lena Petrova, General Practitioner