Chronic pain not only causes physical pain to patients, but also produces psychological reactions, especially depression, which greatly affects the recovery of chronic pain patients. In general, acute pain leads to anxiety, while chronic pain, with the prolongation of time, patients repeatedly go to many hospitals and receive a variety of treatments are not satisfied, it is possible to lose confidence in the ability to cure the disease, based on anxiety, followed by depression, and even depression becomes the main mental disorder. As depression and pain interact with each other, a vicious cycle can be formed, i.e., pain → depression → lower pain threshold → increased pain → severe depression [1]. Once patients develop depressive mood, they may become resistant to medical staff and treatment options, which in turn affects the treatment of the painful disease itself; in addition, because of the unstable psychological state of patients, the incidence of doctor-patient conflict and patient suicide is greatly increased, which will make treatment more difficult.
The prevalence of depressive mood in chronic pain patients is mostly between 17.8% and 92.4% [2-5], and the results of a multicenter cross-sectional epidemiological survey of 246 chronic pain patients showed that the prevalence of depressive mood was 38.62% [6].
In chronic pain patients with combined depressed mood, treating only pain without recognizing and treating depressed mood makes it difficult to relieve pain in a fundamentally rapid and effective manner; the analgesic efficacy is significantly improved when depressed mood is valued and actively treated. Therefore, the treatment of depressed mood is an important part of chronic pain treatment.
I. Goals of depressed mood treatment
(a) To improve the apparent efficiency and clinical cure rate, and to minimize the disability and suicide rate.
(b) To improve the quality of survival, restore social function, and achieve a true cure.
(C), to prevent relapse.
II. Commonly used antidepressants.
Treatment of depression in patients with chronic pain: ① somatic treatment: abandon the cause of pain as soon as possible and completely cure the original disease; if the cause cannot be identified temporarily, effective analgesic measures should be used, such as the application of drugs, nerve blocks and other methods to relieve the patient of pain first. ②Psychotherapy: such as through analytical therapy, cognitive therapy, supportive therapy and other methods, so that the patient can truly experience that doctors and nurses care about and consider his or her suffering and are doing their best to actively treat him or her, thus helping the patient to build up confidence in overcoming the disease. ③ Antidepressant medication: Antidepressant medication refers to the drugs mainly used to treat depressive mental disorders, which do not affect the mood of normal people.
Clinically used antidepressants.
(a), tricyclic antidepressants (TCAs).
1, commonly used drugs: Doxepin (Doxepin), amitriptyline, promethazine, chlorpromazine.
2, mechanism of action: ① M1 receptor blocking effect, ② α receptor blocking effect, ③ H1 receptor blocking effect, ④ inhibit the re-uptake of 5-HT, ⑤ inhibit the re-uptake of NE.
3.Common adverse reactions and treatment.
(1) Peripheral anticholinergic effects cause adverse reactions Main manifestations: dry mouth, blurred vision, urinary retention, bowel movement.
The main manifestations are: dry mouth, blurred vision, urinary retention, constipation, etc. Treatment: ①Dose can be reduced, changed or discontinued. ②Symptomatic treatment. (3) Neostigmine can be tried to counteract.
(2) Central anticholinergic effects cause adverse reactions often occur in drug overdose or special
Individuals may experience delirium, agitation, myoclonus, chorea or confusion, coma and seizures; some cases may experience delusions, delusions, hallucinations, and may be accompanied by flushing, tachycardia, dilated pupils, sweating, hyperthermia, reduced bowel sounds and other symptoms of the vegetative nervous system.
Treatment: ① Discontinue the drug for close observation. ②A state of agitation, delirium or convulsions can be given diazepam 5-10mg, intramuscularly. (3) In a state of confusion or shallow coma, give toxic lentil base 1mg, intravenous slow push or intramuscular injection, 1~2mg per hour. (4) General symptomatic or supportive therapy.
(3) Cardiovascular adverse reactions
(1) Postural hypotension and sinus tachycardia are common, mostly due to blockade of α1-adrenergic receptors, and generally do not require special treatment, keep the patient lying down and observe closely.
(2) Quinidine-like adverse reactions may occur in patients with occult heart disease; the effect on the cardiac conduction system may be Ⅰ to Ⅲ degree atrioventricular block, bundle branch block or intraventricular block, which may be accompanied by prolonged myocardial repolarization process, secondary atrial premature beats, atrial flutter or ventricular rhythm disturbance.
Treatment: Immediate discontinuation of the drug, cardiac monitoring, and symptomatic management.
Prevention: Strictly exclude contraindications before using the drug.
(4) Metabolic reactions are rare.
Treatment: Immediate discontinuation, symptomatic anti-allergic treatment, and hormone treatment in severe cases.
(5) Other adverse reactions include weight gain, change in libido and other metabolic and endocrine disorders. The teratogenic effect has not been determined, and the use is prohibited in the first three months of pregnancy.
(2) Monoamine oxidase inhibitors (MAOIs).
1.Commonly used drugs: phenelzine, moclobemide.
2, mechanism of action: inhibit the activity of MAO and other enzymes, reduce the breakdown of central monoamine transmitters, in order to increase the concentration of monoamine transmitters in the synaptic gap.
3, common adverse reactions and treatment mainly for hypertensive crisis and hepatotoxic effects caused by the combination with TCAs. The treatment is based on prevention.
(C) selective 5-hydroxytryptamine reuptake inhibitors (SSRIs): SSRIs are currently the most commonly used antidepressants.
1.Commonly used drugs: fluoxetine (Pepto-Bismol), paroxetine (Sellett), fluvoxamine (fluvoxamine, LanShi), sertraline (sertraline, Zoloft), citalopram (citalopram, Cipro).
2, mechanism of action: selectively inhibit the reuptake of presynaptic membrane 5-hydroxytryptamine, increase the concentration of pentazocine in the synaptic gap, play the antidepressant effect.
3, common advantages of SSRI drugs.
The characteristics of SSRIs can be summarized as STEPS:
S (Safety): low side effects and good safety.
T(Tolerability): good tolerability and high safety.
E(Efficacy): efficacy in the range of 70%.
P(Payment): more expensive for single dose, but not more expensive than tricyclics and heterocyclics according to the course of treatment.
S (Simplicity): easy to use.
(D), 5-hydroxytryptamine reuptake enhancers.
1.Commonly used drugs: Datilan (tianeptine)
2, mechanism of action: increase the spontaneous activity of hippocampal pyramidal cells and accelerate the recovery of their function after inhibition; increase the reuptake of 5-hydroxytryptamine by neurons in the cerebral cortex and hippocampus.
3.Adverse effects are rare and generally not serious. May appear anorexia, dry mouth, nausea, vomiting, abdominal distension, abdominal pain, constipation; insomnia, dizziness, headache, etc.
(v), 5-hydroxytryptamine (5-HT) and norepinephrine (NE) reabsorption dual inhibitors (SNRIs).
1, commonly used drugs: venlafaxine hydrochloride extended-release capsules, trade name Enox, is the world’s first 5-HT and NE dual reuptake inhibitors (SNRIs), the first FDA-approved antidepressant for the treatment of generalized anxiety (GAD).
2.Mechanism of action: dose-dependent monoamine pharmacological profile