Table 3.

Description of interventions/treatment

Study	Intervention	Description of the intervention	Practitioners delivering the intervention	Duration and intensity of intervention delivery
1. Brodsky, 2021 [53]	Post-COVID-19 myalgic-encephalomyelitis (post-COVID-19 ME) program	Multiple components related to diet, pain management, breathing, and lifestyle interventions (e.g., walking, sleep hygiene, and CBT)	Medical doctors	Weekly for 4 weeks (with certain aspects, e.g., walking, diet and sleep, practised daily)
2. Bogolepova et al., 2021 [51]	Cholytilin and MexiB 6	Two study groups: participants with anxiety/depression dominance received MexiB 6; participants with cognitive impairment dominance received Cholytilin	NR	MexiB 6: One tablet 3 × day Cholytilin: 2 capsules (800 mg) AM, 1 capsule (400 mg) PM Follow up period was 60 days
3. Tereshin et al., 2021 [52],	Intravenous Cytoflavin in combination with a standard rehabilitation program	Control group received a standard post-COVID rehabilitation programme (included pulse magnetic therapy, inhalation therapy, aeroion therapy, aerobic training, psychotherapy, nutritional supplementation, and standard drug therapy). In addition to standard care, intervention group received intravenous Cytoflavin	Cytoflavin: NR Rehabilitation program: some aspects NR, however included a medical psychologist and psychotherapist for psychotherapy component	Cytoflavin: Daily for 10 days Rehabilitation program: 21 ± 2 days
4. Fowler-Davis et al., 2021 [54],	Rehabilitation intervention (LC support sessions)	A co-produced virtual ‘clinic’ delivered by a team of practitioners who met participants three times each to directly consider their needs and offer structured advice	Sport and exercise medicine doctor, an occupational therapist, clinical psychologist or physiotherapist	Three sessions delivered over 3–6 weeks (first two sessions delivered over consecutive weeks and third sessions delivered 2–3 weeks later)
5. Harenwall et al., 2021 [55],	Primary Care Wellbeing Service (PCWBS) “Recovering from COVID” rehabilitation course	Virtually delivered psychoeducation and support that focused on enhancing several health areas affected by LC, including sleep, diet, voice, activity, energy, stress management, breathing, and relapse planning	A clinical psychologist, physiotherapist, occupational therapist, dietitian, speech and language therapist, assistant psychologist, and a personal support navigator	One 60 min virtual session per week for 7 consecutive weeks
6. Łuckoś et al., 2021 [56]	Neurotherapy	Two treatment programmes: administration of neurofeedback (programme A); goal-oriented cognitive training (programme B), which included various strategies (e.g., organising sleep, exercise, healthy diet, maintaining social contacts)	Neuropsychologist, neurorehabilitation, locomotor disorder clinic	Twice a week for 15 weeks (both treatments)
7. Compagno et al., 2022 [57]	Out-of-hospital multidisciplinary rehabilitation (MDR) program	Assessment, physical training, tailored psychosocial treatment (based on cognitive behavioral therapy, eye movement desensitization and reprocessing therapy, with individual relaxation techniques and, multidisciplinary counselling for lifestyle modification)	Multidisciplinary team including physical trainers, nurses, cardiologists, psychologists, and sport medicine physicians	Physical training: 3 90-min sessions/week, range 8–20 sessions; Psychological treatment: 4 sessions
8. Esin et al., 2022 [50]	Anvifen (GABAergic nootropic drug with an anxiolytic effect)	Participants were divided into three groups:     - Group 1: treated with Anvifen at home;     - Group 2: treated with Anvifen in a hospital without oxygen support;     - Group 3: treated with Anvifen in a hospital with oxygen support	NR	500 mg three times a day for 21 days
9. Brough et al., 2022 [58]	A package of care	Group practical and psychoeducational sessions with optional physiotherapy or Craniosacral Therapy (CST), after-care package (e.g., aromatherapy product, mindfulness coloring book, herbal tea, service information)	Health practitioner specialised in CST, a physiotherapist and other facilitators specialised in delivering other sessions	Group sessions: One per week for 4–6 weeks Physiotherapy: two 45 min sessions; CST: up to four 1 h sessions
10. Wagner et al., 2022 [59]	Pulsed electromagnetic field (PEMF)	PEMF treatment using a certified therapy device	NR	Twice weekly for 5 weeks
11. Garcia-Molina et al., 2022 [60]	Outpatient neuropsychological intervention programme	Respiratory therapy, physiotherapy, virtual neuropsychological rehabilitation (which included cognitive treatment), emotional intervention; artificial intelligence algorithms used to create a personalised plan based on the results of the pre-treatment evaluation	Clinical psychologists specialised in neuropsychology	Five sessions per week for 8 weeks (average of four sessions per week)
12. Philip et al., 2022 [61]	English National Opera (ENO) Breathe	A group online delivered breathing and wellbeing programme focused on breathing re-training through singing techniques and utilising lullabies, with access to online resources and regular email contact	LC clinic team including voice specialists	Once a week for 6 weeks (core group intervention), plus self-directed activities
13. Tobinick et al., 2022 [62]	Peri-spinal etanercept	Peri-spinal administration of etanercept	An internal medicine medical practitioner	Single 25 mg dose
14. Wang et al., 2022 [63]	High-fibre formula	Nutritional supplementation using a high fibre formula	NR	Gradual increase in high-fibre diet to three times a day for 2 months
15. Skilbeck, 2022 [64]	Cognitive Behavioural Therapy (CBT)	Virtual CBT sessions including psychoeducation, understanding current symptoms, normalisation and acceptance, goal setting, symptom monitoring, graded activity pacing, measuring patient progress, positive reinforcements, physical and psychological symptoms, reviewing goals, and moving forward	An accredited CBT therapist supervised by an accredited senior CBT therapist and long-term health conditions specialist	12 sessions over 5 months (Intensity NR)
16. Orendáčová et al., 2022 [65]	Neurofeedback (NFB)	Five sessions of NFB (included locating electrodes on the right and left temporal lobes)	A certified neurofeedback therapist	2 weeks: Two NFB sessions delivered at first week and three at the second week (25–45 min sessions)
17. Koliadenko et al., 2022 [66]	Virtual medical consultative psychological and psychiatric therapy	CBT protocols for generalized anxiety disorder and hypochondriacal disorder in combination with antidepressants and nonbenzodiazepine tranquilizer	NR	NR