M

r/MCAS

Founded January 2013 · Public — anyone can post

Updated Sep 1

A science-focused sub for Mast Cell Activation Disorders. Please note: The content on this subreddit is not intended as, and is not a substitute for, medical advice or diagnosis. It must not be interpreted as such. You are strongly advised to consult your own qualified healthcare professionals for any medical questions or concerns.

Members

56,241

56K

Online now

not captured in the last snapshot

Posts per day

36.6

from the last 100 posts, spanning 2.7 days

Comments per post

no sample yet

Growth · 7d

not enough history yet

Growth · 30d

not enough history yet

Promo tolerance

not assessed yet

Last post

Sep 1

sampled Sep 1

Distinct posters

98%

of the last 100 posts

Tracking since Sep 1 · growth spans are the real distance between snapshots, not rounded windows. Posts/day is measured from the community’s own newest posts on Reddit, not from what Prowlo happens to crawl.

Member growth

Tracking since Sep 1 — growth charts appear after a week of history.

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r/MCAS — frequently asked

How many members does r/MCAS have?

r/MCAS has 56,241 members as of our most recent crawl on Sep 1. Prowlo re-checks tracked communities on a rolling schedule, so this figure moves rather than sitting frozen at whatever it was when a scraper last ran.

Is r/MCAS growing?

We don't have 30 days of snapshot history for r/MCAS yet, so we're not going to invent a growth number. We've been tracking it since Sep 1; the chart fills in as history accumulates.

How active is r/MCAS?

Around 36.6 posts per day, measured from the newest 100 posts on Reddit, which span 2.7 days. Posting rate matters more than subscriber count when you're deciding where to spend your time — it determines how long your comment stays visible.

When was r/MCAS created?

r/MCAS was founded in January 2013 and is a public — anyone can post community. Age matters: an older community with steady growth has survived Reddit's moderation churn; a young one with a spike may not.

Who posts in r/MCAS?

Of the last 100 posts we sampled, 98% came from distinct accounts; the newest was published Sep 1. A low share means a feed dominated by a handful of accounts (bots, mods, or one prolific poster) rather than a community.

Can I promote my product in r/MCAS?

We don't have a promo-tolerance read for r/MCAS yet. Default to the safe approach: read the sidebar rules, contribute in threads where you gain nothing, and mention your product only when it is the honest answer to someone's question.

How do I monitor r/MCAS for mentions?

Hit Watch on this page. Prowlo starts crawling r/MCAS into your Dataset — every new post indexed and embedded, searchable semantically, queryable by your AI agent over MCP, and able to trigger keyword alerts in Slack. Prowlo is read-only; it never posts on your behalf.

Can my AI agent read r/MCAS's stats?

Yes. Everything on this page is one MCP tool call away: catalog_get_subreddit returns r/MCAS's members, growth, promo tolerance and similar communities as typed JSON — free, no credits. Connect your agent to api.prowlo.com/mcp and it can vet the community and start watching it in the same conversation.

Watch these subreddits

Rankings go stale. Prowlo watches these subreddits daily and pings you the moment someone describes the problem you solve.

r/SaaS · 4m ago

“Our analytics bill tripled overnight. Actively shopping for an alternative this week — what’s good?”

Match · 86%Buying signal

Read-only · Human-in-the-loop
Prowlo never posts for you

r/MCAS: 56.2K members, 36.6 posts/day (Sep 2026)