Brief Answer:
Need GI work up, IBS suspicions

Detailed Answer:
Thank you for asking!
COnstipation alternating with diarrhoea and vomiting and abdominal pain is a classic presentation of a functional bowel like IBS. . i would like you to seek a gastroenterologist for further work up as there are thousands of etiologies possible for it. washout techniques, radiography and breath tests., CT volumetry and some other GI functional assessment would make things clear for the etiology.
. Intolerance to lactose, fructose and sorbitol are relatively common and thus lipids intake should be minimized to the minimum to avoid such troubles. Bifidobacteria and associated probiotics have proved useful and helpful in the issues.
Also prokinesis and peristalsis of GI tract once impaired may also cause the bloating.
Postprandial bloating is a hallmark of an inflammatory bowel disease and it needs to be assessed by a gastroenterologist and treated accordingly to permanently have a solution for it.
In nut shell, Diet and lifestyle modifications for the functional Gi troubles, More fibres, less fats and carbohydrates, small meals of frequent durations that few larger ones, use of healthy lifestyle and exercise, losing weight if an issue, controlling lipid profile in a limit and compliantly using hypertensive medicines and staying in touch with your doctor is advised.
Fiber supplementation improve symptoms of constipation and diarrhea. Polycarbophil compounds (eg, Citrucel, FiberCon) may produce less flatulence than psyllium compounds (eg, Metamucil).

Judicious water intake is recommended and should be followed. Minimum of 2 litres in a day is advised.

Caffeine avoidance may limit anxiety and symptom exacerbation. Legume avoidance may decrease abdominal bloating. Lactose and/or fructose should be limited or avoided Take care to supplement calcium in patients limiting lactose intake.

Gluten intolerance has been further associated with irritable bowel syndrome. so try gluten free diet and see if it helps.
Meanwhile some prokinetics like metoclopramide and domperidone and erythromycins would keep the propelling work and make the bloating less but it needs a work up as i mentioned to sort out the most likely functional cause as IBS etc.
remember for constipation, The key to treating most patients with constipation is correction of dietary deficiencies, which generally involves increasing intake of fiber and fluid and decreasing the use of constipating agents (eg, milk products, coffee, tea, alcohol).

Medications to treat constipation include the following:

Bulk-forming agents (fibers; eg, psyllium): arguably the best and least expensive medication for long-term treatment
Emollient stool softeners (eg, docusate): Best used for short-term prophylaxis (eg, postoperative)
Rapidly acting lubricants (eg, mineral oil): Used for acute or subacute management of constipation
Prokinetics (eg, tegaserod): Proposed for use with severe constipation-predominant symptoms
Stimulant laxatives (eg, senna): Over-the-counter agents commonly but inappropriately used for long-term treatment of constipation
Newer therapies for constipation include the following:

Prucalopride, a prokinetic selective 5-hydroxytryptamine-4 (5-HT4) receptor antagonist that stimulates colonic motility and decreases transit time
The osmotic agents lubiprostone and linaclotide,which are FDA approved for chronic idiopathic constipation, constipation caused by irritable bowel syndrome, and (in the case of lubiprostone) opioid-induced constipation in adults with chronic, noncancer pain
Get to your gastroenterologist and discuss some newer advancements like sacral nerve stimulation and some surgical interventions if need be with them and let them decide what is best for you.
Seek a gastroenterologist for further management.
I hope it helps. Take good care of yourself and don't forget to close the discussion please.
Regards
S Khan

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